diff --git a/.gitignore b/.gitignore
index 0e1f044..6cf16b2 100644
--- a/.gitignore
+++ b/.gitignore
@@ -22,3 +22,6 @@ DerivedData
 
 # Bundler
 .bundle
+
+# Code Signing Settings
+Example/DevelopmentTeam.xcconfig
diff --git a/.travis.yml b/.travis.yml
index 609768a..693dd61 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,5 +1,5 @@
 language: objective-c
-osx_image: xcode8.3
+osx_image: xcode10.0
 cache: cocoapods
 podfile: Example/Podfile
 notifications:
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..8f96989
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,16 @@
+# IRLSize Change Log
+
+## [2.0.0](https://github.com/detroit-labs/IRLSize/releases/tag/2.0.0)
+**Released:** 2018-11-06
+
+### Breaking Changes
+  - Renamed `IRLRawLengthMeasurement` to `IRLRawMillimeters`
+  - All measurements are now in terms of millimeters
+  - Updated deployment target to iOS 10.0 and watchOS 3.0.
+
+### Updated
+  - Re-sourced all device size data from [official Apple documentation](https://developer.apple.com/accessories)
+  - Refactored test suite to have much less repeated code.
+
+### Fixed
+  - Fixed incorrect values for landscape devices
diff --git a/Example/IRLSizeExample-Watch Extension/ExtensionDelegate.h b/Example/IRLSizeExample-Watch Extension/ExtensionDelegate.h
index 1f14302..cc8ca88 100644
--- a/Example/IRLSizeExample-Watch Extension/ExtensionDelegate.h	
+++ b/Example/IRLSizeExample-Watch Extension/ExtensionDelegate.h	
@@ -3,7 +3,7 @@
 //  IRLSizeExample-Watch Extension
 //
 //  Created by Jeff Kelley on 6/29/2016.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import <WatchKit/WatchKit.h>
diff --git a/Example/IRLSizeExample-Watch Extension/ExtensionDelegate.m b/Example/IRLSizeExample-Watch Extension/ExtensionDelegate.m
index d92ba4a..23e7ac1 100644
--- a/Example/IRLSizeExample-Watch Extension/ExtensionDelegate.m	
+++ b/Example/IRLSizeExample-Watch Extension/ExtensionDelegate.m	
@@ -3,7 +3,7 @@
 //  IRLSizeExample-Watch Extension
 //
 //  Created by Jeff Kelley on 6/29/2016.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import "ExtensionDelegate.h"
diff --git a/Example/IRLSizeExample-Watch Extension/Info.plist b/Example/IRLSizeExample-Watch Extension/Info.plist
index ee0d154..f662752 100644
--- a/Example/IRLSizeExample-Watch Extension/Info.plist	
+++ b/Example/IRLSizeExample-Watch Extension/Info.plist	
@@ -17,7 +17,7 @@
 	<key>CFBundlePackageType</key>
 	<string>XPC!</string>
 	<key>CFBundleShortVersionString</key>
-	<string>1.3.0</string>
+	<string>2.0.0</string>
 	<key>CFBundleSignature</key>
 	<string>????</string>
 	<key>CFBundleVersion</key>
diff --git a/Example/IRLSizeExample-Watch Extension/InterfaceController.h b/Example/IRLSizeExample-Watch Extension/InterfaceController.h
index 57295bb..7b6d7e6 100644
--- a/Example/IRLSizeExample-Watch Extension/InterfaceController.h	
+++ b/Example/IRLSizeExample-Watch Extension/InterfaceController.h	
@@ -3,7 +3,7 @@
 //  IRLSizeExample-Watch Extension
 //
 //  Created by Jeff Kelley on 6/29/2016.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import <WatchKit/WatchKit.h>
diff --git a/Example/IRLSizeExample-Watch Extension/InterfaceController.m b/Example/IRLSizeExample-Watch Extension/InterfaceController.m
index fd282b4..ef460a9 100644
--- a/Example/IRLSizeExample-Watch Extension/InterfaceController.m	
+++ b/Example/IRLSizeExample-Watch Extension/InterfaceController.m	
@@ -3,7 +3,7 @@
 //  IRLSizeExample-Watch Extension
 //
 //  Created by Jeff Kelley on 6/29/2016.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import "InterfaceController.h"
diff --git a/Example/IRLSizeExample-Watch/Info.plist b/Example/IRLSizeExample-Watch/Info.plist
index 8c6cd2e..8674790 100644
--- a/Example/IRLSizeExample-Watch/Info.plist
+++ b/Example/IRLSizeExample-Watch/Info.plist
@@ -17,7 +17,7 @@
 	<key>CFBundlePackageType</key>
 	<string>APPL</string>
 	<key>CFBundleShortVersionString</key>
-	<string>1.3.0</string>
+	<string>2.0.0</string>
 	<key>CFBundleSignature</key>
 	<string>????</string>
 	<key>CFBundleVersion</key>
diff --git a/Example/IRLSizeExample.xcodeproj/project.pbxproj b/Example/IRLSizeExample.xcodeproj/project.pbxproj
index b02a675..ff04763 100644
--- a/Example/IRLSizeExample.xcodeproj/project.pbxproj
+++ b/Example/IRLSizeExample.xcodeproj/project.pbxproj
@@ -99,16 +99,18 @@
 		1F5EC3871D241DBF0068E86F /* ExtensionDelegate.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = ExtensionDelegate.m; sourceTree = "<group>"; };
 		1F5EC3891D241DBF0068E86F /* Assets.xcassets */ = {isa = PBXFileReference; lastKnownFileType = folder.assetcatalog; path = Assets.xcassets; sourceTree = "<group>"; };
 		1F5EC38B1D241DBF0068E86F /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
+		1F8A1FE821923170006ED4EC /* SigningSettings.xcconfig */ = {isa = PBXFileReference; lastKnownFileType = text.xcconfig; path = SigningSettings.xcconfig; sourceTree = "<group>"; };
 		1FBC8FD31D236DFD00015A75 /* IRLSizeExample-Bridging-Header.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "IRLSizeExample-Bridging-Header.h"; sourceTree = "<group>"; };
 		1FBC8FD41D236DFD00015A75 /* RulerView.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = RulerView.swift; sourceTree = "<group>"; };
 		1FC7E2001D5F99D400274C2A /* NSMeasurement+Equality.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = "NSMeasurement+Equality.h"; sourceTree = "<group>"; };
 		1FC7E2011D5F99D400274C2A /* NSMeasurement+Equality.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = "NSMeasurement+Equality.m"; sourceTree = "<group>"; };
 		1FC7E2031D5F9EB500274C2A /* IRLMeasurementBeWithinMatcher.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = IRLMeasurementBeWithinMatcher.h; sourceTree = "<group>"; };
 		1FC7E2041D5F9EB500274C2A /* IRLMeasurementBeWithinMatcher.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = IRLMeasurementBeWithinMatcher.m; sourceTree = "<group>"; };
+		1FD4587321913DD500982651 /* CHANGELOG.md */ = {isa = PBXFileReference; lastKnownFileType = net.daringfireball.markdown; name = CHANGELOG.md; path = ../CHANGELOG.md; sourceTree = "<group>"; };
 		2D7A6FA6D99E271DC58A3FDB /* Pods-IRLSizeExample.release.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-IRLSizeExample.release.xcconfig"; path = "Pods/Target Support Files/Pods-IRLSizeExample/Pods-IRLSizeExample.release.xcconfig"; sourceTree = "<group>"; };
 		3B52ABAB0F4897702004A1C3 /* Pods-IRLSizeExample.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-IRLSizeExample.debug.xcconfig"; path = "Pods/Target Support Files/Pods-IRLSizeExample/Pods-IRLSizeExample.debug.xcconfig"; sourceTree = "<group>"; };
 		3F468B881C59569556F61E7D /* Pods-IRLSizeExample-Watch Extension.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-IRLSizeExample-Watch Extension.debug.xcconfig"; path = "Pods/Target Support Files/Pods-IRLSizeExample-Watch Extension/Pods-IRLSizeExample-Watch Extension.debug.xcconfig"; sourceTree = "<group>"; };
-		41B6AD569D60E1A0310A509C /* IRLSize.podspec */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text; name = IRLSize.podspec; path = ../IRLSize.podspec; sourceTree = "<group>"; };
+		41B6AD569D60E1A0310A509C /* IRLSize.podspec */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text; name = IRLSize.podspec; path = ../IRLSize.podspec; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.ruby; };
 		5BEF1258540BA1981AF80DB5 /* libPods-IRLSizeExample-Watch Extension.a */ = {isa = PBXFileReference; explicitFileType = archive.ar; includeInIndex = 0; path = "libPods-IRLSizeExample-Watch Extension.a"; sourceTree = BUILT_PRODUCTS_DIR; };
 		6003F58A195388D20070C39A /* IRLSizeExample.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = IRLSizeExample.app; sourceTree = BUILT_PRODUCTS_DIR; };
 		6003F58D195388D20070C39A /* Foundation.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = Foundation.framework; path = System/Library/Frameworks/Foundation.framework; sourceTree = SDKROOT; };
@@ -199,6 +201,8 @@
 		6003F581195388D10070C39A = {
 			isa = PBXGroup;
 			children = (
+				1F8A1FE821923170006ED4EC /* SigningSettings.xcconfig */,
+				1FD4587321913DD500982651 /* CHANGELOG.md */,
 				60FF7A9C1954A5C5007DD14C /* Podspec Metadata */,
 				6003F593195388D20070C39A /* IRLSizeExample */,
 				6003F5B5195388D20070C39A /* IRLSizeTests */,
@@ -270,7 +274,8 @@
 				6003F5BB195388D20070C39A /* IRLSizeTests.m */,
 				6003F5B6195388D20070C39A /* Supporting Files */,
 			);
-			path = IRLSizeTests;
+			name = IRLSizeTests;
+			path = ../IRLSizeTests;
 			sourceTree = SOURCE_ROOT;
 		};
 		6003F5B6195388D20070C39A /* Supporting Files */ = {
@@ -686,6 +691,7 @@
 		};
 		6003F5BD195388D20070C39A /* Debug */ = {
 			isa = XCBuildConfiguration;
+			baseConfigurationReference = 1F8A1FE821923170006ED4EC /* SigningSettings.xcconfig */;
 			buildSettings = {
 				ALWAYS_SEARCH_USER_PATHS = NO;
 				CLANG_CXX_LANGUAGE_STANDARD = "gnu++0x";
@@ -740,6 +746,7 @@
 		};
 		6003F5BE195388D20070C39A /* Release */ = {
 			isa = XCBuildConfiguration;
+			baseConfigurationReference = 1F8A1FE821923170006ED4EC /* SigningSettings.xcconfig */;
 			buildSettings = {
 				ALWAYS_SEARCH_USER_PATHS = NO;
 				CLANG_CXX_LANGUAGE_STANDARD = "gnu++0x";
@@ -839,7 +846,7 @@
 					"DEBUG=1",
 					"$(inherited)",
 				);
-				INFOPLIST_FILE = "IRLSizeTests/IRLSizeTests-Info.plist";
+				INFOPLIST_FILE = "../IRLSizeTests/IRLSizeTests-Info.plist";
 				PRODUCT_BUNDLE_IDENTIFIER = "com.detroitlabs.demo.${PRODUCT_NAME:rfc1034identifier}";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				WRAPPER_EXTENSION = xctest;
@@ -855,7 +862,7 @@
 					"$(inherited)",
 					"$(DEVELOPER_FRAMEWORKS_DIR)",
 				);
-				INFOPLIST_FILE = "IRLSizeTests/IRLSizeTests-Info.plist";
+				INFOPLIST_FILE = "../IRLSizeTests/IRLSizeTests-Info.plist";
 				PRODUCT_BUNDLE_IDENTIFIER = "com.detroitlabs.demo.${PRODUCT_NAME:rfc1034identifier}";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				WRAPPER_EXTENSION = xctest;
diff --git a/Example/IRLSizeExample/IRLAppDelegate.h b/Example/IRLSizeExample/IRLAppDelegate.h
index 33ebb63..c6f367a 100644
--- a/Example/IRLSizeExample/IRLAppDelegate.h
+++ b/Example/IRLSizeExample/IRLAppDelegate.h
@@ -3,7 +3,7 @@
 //  IRLSizeExample
 //
 //  Created by Jeff Kelley on 11/13/2014.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import <UIKit/UIKit.h>
diff --git a/Example/IRLSizeExample/IRLAppDelegate.m b/Example/IRLSizeExample/IRLAppDelegate.m
index 35ff222..0f2f932 100644
--- a/Example/IRLSizeExample/IRLAppDelegate.m
+++ b/Example/IRLSizeExample/IRLAppDelegate.m
@@ -3,7 +3,7 @@
 //  IRLSizeExample
 //
 //  Created by Jeff Kelley on 11/13/2014.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import "IRLAppDelegate.h"
diff --git a/Example/IRLSizeExample/IRLSizeExample-Info.plist b/Example/IRLSizeExample/IRLSizeExample-Info.plist
index 7f768bd..0633b67 100644
--- a/Example/IRLSizeExample/IRLSizeExample-Info.plist
+++ b/Example/IRLSizeExample/IRLSizeExample-Info.plist
@@ -17,7 +17,7 @@
 	<key>CFBundlePackageType</key>
 	<string>APPL</string>
 	<key>CFBundleShortVersionString</key>
-	<string>1.3.0</string>
+	<string>2.0.0</string>
 	<key>CFBundleSignature</key>
 	<string>????</string>
 	<key>CFBundleVersion</key>
diff --git a/Example/IRLSizeExample/IRLViewController.h b/Example/IRLSizeExample/IRLViewController.h
index a0d37a9..8220de7 100644
--- a/Example/IRLSizeExample/IRLViewController.h
+++ b/Example/IRLSizeExample/IRLViewController.h
@@ -3,7 +3,7 @@
 //  IRLSizeExample
 //
 //  Created by Jeff Kelley on 11/13/2014.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import <UIKit/UIKit.h>
diff --git a/Example/IRLSizeExample/IRLViewController.m b/Example/IRLSizeExample/IRLViewController.m
index 025fc11..cf34589 100644
--- a/Example/IRLSizeExample/IRLViewController.m
+++ b/Example/IRLSizeExample/IRLViewController.m
@@ -3,7 +3,7 @@
 //  IRLSizeExample
 //
 //  Created by Jeff Kelley on 11/13/2014.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import "IRLViewController.h"
diff --git a/Example/IRLSizeExample/Launch Screen.xib b/Example/IRLSizeExample/Launch Screen.xib
index 1c76273..59d9d3a 100644
--- a/Example/IRLSizeExample/Launch Screen.xib	
+++ b/Example/IRLSizeExample/Launch Screen.xib	
@@ -1,23 +1,22 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<document type="com.apple.InterfaceBuilder3.CocoaTouch.XIB" version="3.0" toolsVersion="12120" systemVersion="16E195" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" launchScreen="YES" useTraitCollections="YES" colorMatched="YES">
-    <device id="retina4_7" orientation="portrait">
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.XIB" version="3.0" toolsVersion="14460.31" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" launchScreen="YES" useTraitCollections="YES" colorMatched="YES">
+    <device id="retina6_5" orientation="portrait">
         <adaptation id="fullscreen"/>
     </device>
     <dependencies>
         <deployment identifier="iOS"/>
-        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="12088"/>
-        <capability name="Constraints with non-1.0 multipliers" minToolsVersion="5.1"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="14460.20"/>
         <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
     </dependencies>
     <objects>
         <placeholder placeholderIdentifier="IBFilesOwner" id="-1" userLabel="File's Owner"/>
         <placeholder placeholderIdentifier="IBFirstResponder" id="-2" customClass="UIResponder"/>
         <view contentMode="scaleToFill" id="iN0-l3-epB">
-            <rect key="frame" x="0.0" y="0.0" width="375" height="667"/>
+            <rect key="frame" x="0.0" y="0.0" width="414" height="896"/>
             <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
             <subviews>
-                <label opaque="NO" clipsSubviews="YES" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="  Copyright © 2017 Detroit Labs. All rights reserved." textAlignment="center" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" minimumFontSize="9" translatesAutoresizingMaskIntoConstraints="NO" id="8ie-xW-0ye">
-                    <rect key="frame" x="20" y="633.5" width="335" height="13.5"/>
+                <label opaque="NO" clipsSubviews="YES" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="Copyright © 2018 Detroit Labs. All rights reserved." textAlignment="center" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" minimumFontSize="9" translatesAutoresizingMaskIntoConstraints="NO" id="8ie-xW-0ye">
+                    <rect key="frame" x="20" y="862.66666666666663" width="374" height="13.333333333333371"/>
                     <fontDescription key="fontDescription" type="system" pointSize="17"/>
                     <color key="textColor" red="0.0" green="0.0" blue="0.0" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
                     <nil key="highlightedColor"/>
@@ -26,7 +25,7 @@
                     </variation>
                 </label>
                 <label opaque="NO" clipsSubviews="YES" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="IRLSizeExample" textAlignment="center" lineBreakMode="middleTruncation" baselineAdjustment="alignBaselines" minimumFontSize="18" translatesAutoresizingMaskIntoConstraints="NO" id="kId-c2-rCX">
-                    <rect key="frame" x="20" y="202" width="335" height="43"/>
+                    <rect key="frame" x="20" y="278.33333333333331" width="374" height="43"/>
                     <fontDescription key="fontDescription" type="boldSystem" pointSize="36"/>
                     <color key="textColor" red="0.0" green="0.0" blue="0.0" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
                     <nil key="highlightedColor"/>
diff --git a/Example/IRLSizeExample/RulerView.swift b/Example/IRLSizeExample/RulerView.swift
index 961a8b3..7c52051 100644
--- a/Example/IRLSizeExample/RulerView.swift
+++ b/Example/IRLSizeExample/RulerView.swift
@@ -3,7 +3,7 @@
 //  IRLSizeExample
 //
 //  Created by Jeff Kelley on 6/28/2016.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 import Foundation
diff --git a/Example/IRLSizeExample/main.m b/Example/IRLSizeExample/main.m
index 06ef11f..2d4d98b 100644
--- a/Example/IRLSizeExample/main.m
+++ b/Example/IRLSizeExample/main.m
@@ -3,7 +3,7 @@
 //  IRLSizeExample
 //
 //  Created by Jeff Kelley on 11/13/2014.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import <UIKit/UIKit.h>
diff --git a/Example/IRLSizeTests/IRLSizeTests.m b/Example/IRLSizeTests/IRLSizeTests.m
deleted file mode 100644
index 13d0e37..0000000
--- a/Example/IRLSizeTests/IRLSizeTests.m
+++ /dev/null
@@ -1,1682 +0,0 @@
-//
-//  IRLSizeTests.m
-//  IRLSizeTests
-//
-//  Created by Jeff Kelley on 11/13/2014.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
-//
-
-#import <IRLSize/IRLSize.h>
-
-#import <UIKit/UIKit.h>
-
-#import <Kiwi/Kiwi.h>
-#import <SDVersion/SDVersion.h>
-
-#import "IRLMeasurementBeWithinMatcher.h"
-
-SPEC_BEGIN(IRLSizeTests)
-
-describe(@"Getting the native size of a device", ^{
-    
-    registerMatchers(@"IRL");
-    
-    context(@"on an iPhone 4S", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPhone4S)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0740
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0493
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPhone 5", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPhone5)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0885
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0499
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPhone 5C", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPhone5C)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0885
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0499
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPhone 5S", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPhone5S)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0885
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0499
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-    });
-    
-    context(@"on an iPhone SE", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPhoneSE)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0885
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0499
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPhone 6", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPhone6)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1041
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0585
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPhone 6 Plus", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPhone6SPlus)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1218
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0685
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPhone 6s Plus", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPhone6SPlus)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1218
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0685
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPhone 6s", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPhone6S)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1041
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0585
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPhone 7", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPhone7)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1041
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0585
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPhone 7 Plus", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPhone7Plus)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1218
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0685
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPhone 8", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPhone8)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1041
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0585
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPhone 8 Plus", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPhone8Plus)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1218
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0685
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPhone X", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPhoneX)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1351
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.06239
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPad (2nd Generation)", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPad2)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1971
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1478
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPad (3rd Generation)", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPad3)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1971
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1478
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPad (4th Generation)", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPad4)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1971
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1478
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPad mini", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPadMini)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1605
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1204
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPad Air", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPadAir)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1971
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1478
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPad mini (2nd Generation)", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPadMini2)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1605
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1204
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPad Air 2", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPadAir2)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1971
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1478
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPad mini (3rd Generation)", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPadMini3)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1605
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1204
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on a 9.7\" iPad Pro", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPadPro9Dot7Inch)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1971
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1478
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on a 12.9\" iPad Pro", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPadPro12Dot9Inch)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.2622
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1965
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPad mini (4th Generation)", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPadMini4)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1605
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1204
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPad (5th Generation)", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPad5)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1971
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1478
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on a 10.5\" iPad Pro", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPadPro10Dot5Inch)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.2134
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.16
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on a 12.9\" iPad Pro (2nd Generation)", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPadPro12Dot9Inch2Gen)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.2622
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1965
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPod touch (5th Generation)", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPodTouch5Gen)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0885
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0499
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on an iPod touch (6th Generation)", ^{
-        
-        beforeEach(^{
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPodTouch6Gen)];
-            
-        });
-        
-        it(@"should report the correct height", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0885
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should report the correct width", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0499
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-});
-
-describe(@"Estimating the size of an unknown device based on the screen size", ^{
-    
-    registerMatchers(@"IRL");
-    
-    __block UIScreen *mockScreen = nil;
-    __block NSObject <UICoordinateSpace> *mockCoordinateSpace = nil;
-    
-    beforeEach(^{
-        
-        [SDiOSVersion stub:@selector(deviceVersion)
-                 andReturn:theValue(Simulator)];
-        
-        mockScreen = [UIScreen mock];
-        mockCoordinateSpace = [KWMock mockForProtocol:@protocol(UICoordinateSpace)];
-        
-        [UIScreen stub:@selector(mainScreen) andReturn:mockScreen];
-        
-        [mockScreen stub:@selector(fixedCoordinateSpace)
-               andReturn:mockCoordinateSpace];
-        
-    });
-    
-    afterEach(^{
-        
-        mockScreen = nil;
-        
-    });
-    
-    context(@"on a device with a resolution of 320 ⨉ 480", ^{
-        
-        beforeEach(^{
-            
-            [mockCoordinateSpace stub:@selector(bounds)
-                            andReturn:theValue(CGRectMake(0.0f, 0.0f,
-                                                          320.0f, 480.0))];
-            
-        });
-        
-        it(@"should estimate the height of a 3.5\" device", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0740
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should estimate the width of a 3.5\" device", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0493
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on a device with a resolution of 320 ⨉ 568", ^{
-        
-        beforeEach(^{
-            
-            [mockCoordinateSpace stub:@selector(bounds)
-                            andReturn:theValue(CGRectMake(0.0f, 0.0f,
-                                                          320.0f, 568.0f))];
-            
-        });
-        
-        it(@"should estimate the height of a 4\" device", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0885
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should estimate the width of a 4\" device", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0499
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on a device with a resolution of 375 ⨉ 667", ^{
-        
-        beforeEach(^{
-            
-            [mockCoordinateSpace stub:@selector(bounds)
-                            andReturn:theValue(CGRectMake(0.0f, 0.0f,
-                                                          375.0f, 667.0f))];
-            
-        });
-        
-        it(@"should estimate the height of a 4.7\" device", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1041
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should estimate the width of a 4.7\" device", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0585f
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on a device with a resolution of 414 ⨉ 736", ^{
-        
-        beforeEach(^{
-            
-            [mockCoordinateSpace stub:@selector(bounds)
-                            andReturn:theValue(CGRectMake(0.0f, 0.0f,
-                                                          414.0f, 736.0f))];
-            
-        });
-        
-        it(@"should estimate the height of a 5.5\" device", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1218
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should estimate the width of a 5.5\" device", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.0685
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on a device with a resolution of 375 ⨉ 812", ^{
-        
-        beforeEach(^{
-            
-            [mockCoordinateSpace stub:@selector(bounds)
-                            andReturn:theValue(CGRectMake(0.0f, 0.0f,
-                                                          375.0f, 812.0f))];
-            
-        });
-        
-        it(@"should estimate the height of a 5.5\" device", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1351
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should estimate the width of a 5.8\" device", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.06239
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on a device with a resolution of 768 ⨉ 1024", ^{
-        
-        beforeEach(^{
-            
-            [mockCoordinateSpace stub:@selector(bounds)
-                            andReturn:theValue(CGRectMake(0.0f, 0.0f,
-                                                          768.0f, 1024.0f))];
-            
-        });
-        
-        it(@"should estimate the height of a 9.7\" device", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1971
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should estimate the width of a 9.7\" device", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1478
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on a device with a resolution of 834 ⨉ 1112", ^{
-        
-        beforeEach(^{
-            
-            [mockCoordinateSpace stub:@selector(bounds)
-                            andReturn:theValue(CGRectMake(0.0f, 0.0f,
-                                                          834.0f, 1112.0f))];
-            
-        });
-        
-        it(@"should estimate the height of a 10.5\" device", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.2134
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should estimate the width of a 10.5\" device", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.16
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-    context(@"on a device with a resolution of 1024 ⨉ 1366", ^{
-        
-        beforeEach(^{
-            
-            [mockCoordinateSpace stub:@selector(bounds)
-                            andReturn:theValue(CGRectMake(0.0f, 0.0f,
-                                                          1024.0f, 1366.0f))];
-            
-        });
-        
-        it(@"should estimate the height of a 12.9\" device", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedHeight =
-            [[NSMeasurement alloc] initWithDoubleValue:0.2622
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenHeight should]
-             beWithin:0.01
-             ofMeasurement:expectedHeight];
-            
-        });
-        
-        it(@"should estimate the width of a 12.9\" device", ^{
-            
-            NSMeasurement<NSUnitLength *> *expectedWidth =
-            [[NSMeasurement alloc] initWithDoubleValue:0.1965
-                                                  unit:[NSUnitLength meters]];
-            
-            [[UIDevice.currentDevice.irl_physicalScreenWidth should]
-             beWithin:0.01
-             ofMeasurement:expectedWidth];
-            
-        });
-        
-    });
-    
-});
-
-describe(@"Getting the IRL size of a view", ^{
-    
-    registerMatchers(@"IRL");
-    
-    __block UIApplication *mockSharedApplication;
-    __block UIScreen *mockMainScreen;
-    __block UIWindow *mockWindow;
-    
-    beforeEach(^{
-        
-        mockMainScreen = [UIScreen mock];
-        
-        [UIScreen stub:@selector(mainScreen)
-             andReturn:mockMainScreen];
-        
-        mockWindow = [UIWindow mock];
-        
-        [mockWindow stub:@selector(screen)
-               andReturn:mockMainScreen];
-        
-        mockSharedApplication = [UIApplication mock];
-        
-        [mockSharedApplication stub:@selector(statusBarOrientation)
-                          andReturn:theValue(UIInterfaceOrientationPortrait)];
-        
-        [mockSharedApplication stub:@selector(keyWindow)
-                          andReturn:mockWindow];
-        
-        [UIApplication stub:@selector(sharedApplication)
-                  andReturn:mockSharedApplication];
-        
-        [mockWindow stub:@selector(convertRect:fromView:)
-               withBlock:^id(NSArray *params) {
-                   NSValue *frameValue = params[0];
-                   
-                   CGRect frame = [frameValue CGRectValue];
-                   
-                   return theValue(frame);
-               }];
-        
-    });
-    
-    context(@"on an iPhone 6s", ^{
-        
-        __block UIView *view;
-        
-        beforeEach(^{
-            
-            CGRect iPhone6sBounds = CGRectMake(0.0f, 0.0f,
-                                               375.0f, 667.0f);
-            
-            KWMock <UICoordinateSpace> *mockFixedCoordinateSpace =
-            [KWMock mockForProtocol:@protocol(UICoordinateSpace)];
-            
-            [mockFixedCoordinateSpace stub:@selector(bounds)
-                                 andReturn:theValue(iPhone6sBounds)];
-            
-            [mockMainScreen stub:@selector(fixedCoordinateSpace)
-                       andReturn:mockFixedCoordinateSpace];
-            
-            [mockMainScreen stub:@selector(bounds)
-                       andReturn:theValue(iPhone6sBounds)];
-            
-            [SDiOSVersion stub:@selector(deviceVersion)
-                     andReturn:theValue(iPhone6S)];
-            
-            [mockWindow stub:@selector(bounds)
-                   andReturn:theValue(iPhone6sBounds)];
-            
-            view = [[UIView alloc] initWithFrame:CGRectMake(0.0f,
-                                                            0.0f,
-                                                            100.0f,
-                                                            100.0f)];
-            
-        });
-        
-        context(@"when a view is on the main screen", ^{
-            
-            beforeEach(^{
-                
-                [view stub:@selector(window) andReturn:mockWindow];
-                [view stub:@selector(superview) andReturn:mockWindow];
-                
-            });
-            
-            it(@"should report the correct size", ^{
-                
-                NSMeasurement<NSUnitLength *> *expectedSize =
-                [[NSMeasurement alloc] initWithDoubleValue:0.01654589372
-                                                      unit:[NSUnitLength meters]];
-                
-                [[view.irl_physicalWidth should] beWithin:0.01
-                                            ofMeasurement:expectedSize];
-                
-                [[view.irl_physicalHeight should] beWithin:0.01
-                                             ofMeasurement:expectedSize];
-                
-            });
-            
-            it(@"should return the correct transform to resize the view", ^{
-                
-                CGAffineTransform transform =
-                [view irl_transformForPhysicalWidth:
-                 [[NSMeasurement alloc] initWithDoubleValue:0.01
-                                                       unit:[NSUnitLength meters]]];
-                
-                CGAffineTransform expectedTransform =
-                CGAffineTransformMakeScale(0.641025602, 0.641025602);
-                
-                [[theValue(transform.a) should] equal:expectedTransform.a
-                                            withDelta:0.001];
-                
-                [[theValue(transform.d) should] equal:expectedTransform.d
-                                            withDelta:0.001];
-                
-            });
-            
-        });
-        
-        context(@"when a view is not attached to a window", ^{
-            
-            it(@"should report the correct size", ^{
-                
-                NSMeasurement<NSUnitLength *> *expectedSize =
-                [[NSMeasurement alloc] initWithDoubleValue:0.01654589372
-                                                      unit:[NSUnitLength meters]];
-                
-                [[view.irl_physicalWidth should] beWithin:0.01
-                                            ofMeasurement:expectedSize];
-                
-                [[view.irl_physicalHeight should] beWithin:0.01
-                                             ofMeasurement:expectedSize];
-                
-            });
-            
-            it(@"should return the correct transform to resize the view", ^{
-                
-                CGAffineTransform transform =
-                [view irl_transformForPhysicalWidth:
-                 [[NSMeasurement alloc] initWithDoubleValue:0.01f
-                                                       unit:[NSUnitLength meters]]];
-                
-                CGAffineTransform expectedTransform =
-                CGAffineTransformMakeScale(0.641025602, 0.641025602);
-                
-                [[theValue(transform.a) should] equal:expectedTransform.a
-                                            withDelta:0.001];
-                
-                [[theValue(transform.d) should] equal:expectedTransform.d
-                                            withDelta:0.001];
-                
-            });
-            
-        });
-        
-        context(@"when there is no key window", ^{
-            
-            beforeEach(^{
-                
-                [UIApplication.sharedApplication stub:@selector(keyWindow)
-                                            andReturn:nil];
-                
-            });
-            
-            it(@"should report the correct size", ^{
-                
-                NSMeasurement<NSUnitLength *> *expectedSize =
-                [[NSMeasurement alloc] initWithDoubleValue:0.01654589372
-                                                      unit:[NSUnitLength meters]];
-                
-                [[view.irl_physicalWidth should] beWithin:0.01
-                                            ofMeasurement:expectedSize];
-                
-                [[view.irl_physicalHeight should] beWithin:0.01
-                                             ofMeasurement:expectedSize];
-                
-            });
-            
-            it(@"should return the correct transform to resize the view", ^{
-                
-                CGAffineTransform transform =
-                [view irl_transformForPhysicalWidth:
-                 [[NSMeasurement alloc] initWithDoubleValue:0.01
-                                                       unit:[NSUnitLength meters]]];
-                
-                CGAffineTransform expectedTransform =
-                CGAffineTransformMakeScale(0.641025602, 0.641025602);
-                
-                [[theValue(transform.a) should] equal:expectedTransform.a
-                                            withDelta:0.001];
-                
-                [[theValue(transform.d) should] equal:expectedTransform.d
-                                            withDelta:0.001];
-                
-            });
-            
-            context(@"when the device is rotated to landscape", ^{
-                
-                beforeEach(^{
-                    
-                    [mockSharedApplication stub:@selector(statusBarOrientation)
-                                      andReturn:theValue(UIInterfaceOrientationLandscapeLeft)];
-                    
-                });
-                
-                it(@"should report the correct size", ^{
-                    
-                    NSMeasurement<NSUnitLength *> *expectedSize =
-                    [[NSMeasurement alloc] initWithDoubleValue:0.01654589372
-                                                          unit:[NSUnitLength meters]];
-                    
-                    [[view.irl_physicalWidth should] beWithin:0.01
-                                                ofMeasurement:expectedSize];
-                    
-                    [[view.irl_physicalHeight should] beWithin:0.01
-                                                 ofMeasurement:expectedSize];
-                    
-                    
-                });
-                
-                it(@"should return the correct transform to resize the view", ^{
-                    
-                    CGAffineTransform transform =
-                    [view irl_transformForPhysicalWidth:
-                     [[NSMeasurement alloc] initWithDoubleValue:0.01
-                                                           unit:[NSUnitLength meters]]];
-                    
-                    CGAffineTransform expectedTransform =
-                    CGAffineTransformMakeScale(0.641025602, 0.641025602);
-                    
-                    [[theValue(transform.a) should] equal:expectedTransform.a
-                                                withDelta:0.001];
-                    
-                    [[theValue(transform.d) should] equal:expectedTransform.d
-                                                withDelta:0.001];
-                    
-                });
-                
-            });
-            
-        });
-        
-        context(@"when a view is on a secondary screen", ^{
-            
-            beforeEach(^{
-                
-                UIScreen *mockOtherScreen = [UIScreen mock];
-                UIWindow *mockOtherWindow = [UIWindow mock];
-                
-                [mockOtherWindow stub:@selector(screen)
-                            andReturn:mockOtherScreen];
-                
-                [view stub:@selector(superview)
-                 andReturn:mockOtherWindow];
-                
-                [view stub:@selector(window)
-                 andReturn:mockOtherWindow];
-                
-                [view stub:@selector(transform)
-                 andReturn:theValue(CGAffineTransformIdentity)];
-                
-            });
-            
-            it(@"should not return a size", ^{
-                
-                [[view.irl_physicalWidth should] beNil];
-                [[view.irl_physicalHeight should] beNil];
-                
-            });
-            
-            it(@"should reuse the view’s transform for resizing", ^{
-                
-                NSMeasurement<NSUnitLength *> *desiredWidth =
-                [[NSMeasurement alloc] initWithDoubleValue:0.42
-                                                      unit:[NSUnitLength meters]];
-                
-                CGAffineTransform transform =
-                [view irl_transformForPhysicalWidth:desiredWidth];
-                
-                [[theValue(CGAffineTransformIsIdentity(transform)) should] beTrue];
-                
-            });
-            
-        });
-        
-    });
-    
-});
-
-SPEC_END
diff --git a/Example/Podfile.lock b/Example/Podfile.lock
index 5929a1f..c68ce5e 100644
--- a/Example/Podfile.lock
+++ b/Example/Podfile.lock
@@ -1,5 +1,5 @@
 PODS:
-  - IRLSize (1.2.0):
+  - IRLSize (2.0.0):
     - SDVersion (~> 4.3.0)
   - Kiwi (3.0.0)
   - SDVersion (4.3.2)
@@ -18,10 +18,10 @@ EXTERNAL SOURCES:
     :path: ".."
 
 SPEC CHECKSUMS:
-  IRLSize: de329ea25f24bf525139860191f75cb0212e0afb
+  IRLSize: df0a2b3e2283a5afd600e0bb1656d7f4720b5850
   Kiwi: fbeafef0f00e4d8f7dcb3420a4930afe70af77f7
   SDVersion: 18f32c835c1543611fcfae3c6accd9a04b90597e
 
 PODFILE CHECKSUM: 24be737e1d2c08b86ebee103a00184355b769706
 
-COCOAPODS: 1.5.3
+COCOAPODS: 1.6.0.beta.2
diff --git a/Example/SigningSettings.xcconfig b/Example/SigningSettings.xcconfig
new file mode 100644
index 0000000..b878c52
--- /dev/null
+++ b/Example/SigningSettings.xcconfig
@@ -0,0 +1,21 @@
+//
+//  SigningSettings.xcconfig
+//  IRLSizeExample
+//
+//  Created by Jeff Kelley on 11/6/18.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
+//
+
+// Configuration settings file format documentation can be found at:
+// https://help.apple.com/xcode/#/dev745c5c974
+
+// To add signing settings, create a new file in the Example/ directory with the
+// name “DevelopmentTeam.xcconfig” and the following contents:
+//
+// DEVELOPMENT_TEAM = <TEAM ID HERE>
+//
+// This file will automatically include it and use the settings at build time
+// (You won’t see them reflected in the Xcode UI, but they will work when you
+// build).
+
+#include? "DevelopmentTeam.xcconfig"
diff --git a/Gemfile b/Gemfile
index 4122afb..34ffb91 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,4 +1,4 @@
 source "https://rubygems.org"
 
-gem "cocoapods"
+gem "cocoapods", "~> 1.6.0.beta.1"
 gem "xcpretty"
diff --git a/Gemfile.lock b/Gemfile.lock
index 60eccea..cebee49 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -9,31 +9,31 @@ GEM
       tzinfo (~> 1.1)
     atomos (0.1.3)
     claide (1.0.2)
-    cocoapods (1.5.3)
+    cocoapods (1.6.0.beta.2)
       activesupport (>= 4.0.2, < 5)
       claide (>= 1.0.2, < 2.0)
-      cocoapods-core (= 1.5.3)
+      cocoapods-core (= 1.6.0.beta.2)
       cocoapods-deintegrate (>= 1.0.2, < 2.0)
-      cocoapods-downloader (>= 1.2.0, < 2.0)
+      cocoapods-downloader (>= 1.2.2, < 2.0)
       cocoapods-plugins (>= 1.0.0, < 2.0)
       cocoapods-search (>= 1.0.0, < 2.0)
       cocoapods-stats (>= 1.0.0, < 2.0)
-      cocoapods-trunk (>= 1.3.0, < 2.0)
+      cocoapods-trunk (>= 1.3.1, < 2.0)
       cocoapods-try (>= 1.1.0, < 2.0)
       colored2 (~> 3.1)
       escape (~> 0.0.4)
       fourflusher (~> 2.0.1)
       gh_inspector (~> 1.0)
-      molinillo (~> 0.6.5)
+      molinillo (~> 0.6.6)
       nap (~> 1.0)
-      ruby-macho (~> 1.1)
-      xcodeproj (>= 1.5.7, < 2.0)
-    cocoapods-core (1.5.3)
+      ruby-macho (~> 1.3, >= 1.3.1)
+      xcodeproj (>= 1.7.0, < 2.0)
+    cocoapods-core (1.6.0.beta.2)
       activesupport (>= 4.0.2, < 6)
       fuzzy_match (~> 2.0.4)
       nap (~> 1.0)
     cocoapods-deintegrate (1.0.2)
-    cocoapods-downloader (1.2.1)
+    cocoapods-downloader (1.2.2)
     cocoapods-plugins (1.0.0)
       nap
     cocoapods-search (1.0.0)
@@ -43,7 +43,7 @@ GEM
       netrc (~> 0.11)
     cocoapods-try (1.1.0)
     colored2 (3.1.2)
-    concurrent-ruby (1.0.5)
+    concurrent-ruby (1.1.1)
     escape (0.0.4)
     fourflusher (2.0.1)
     fuzzy_match (2.0.4)
@@ -60,7 +60,7 @@ GEM
     thread_safe (0.3.6)
     tzinfo (1.2.5)
       thread_safe (~> 0.1)
-    xcodeproj (1.6.0)
+    xcodeproj (1.7.0)
       CFPropertyList (>= 2.3.3, < 4.0)
       atomos (~> 0.1.3)
       claide (>= 1.0.2, < 2.0)
@@ -73,8 +73,8 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
-  cocoapods
+  cocoapods (~> 1.6.0.beta.1)
   xcpretty
 
 BUNDLED WITH
-   1.16.5
+   1.17.1
diff --git a/IRLSize.podspec b/IRLSize.podspec
index f514b3a..a5f5952 100644
--- a/IRLSize.podspec
+++ b/IRLSize.podspec
@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name             = "IRLSize"
-  s.version          = "1.3.0"
+  s.version          = "2.0.0"
   s.summary          = "A library for determining the actual physical size of pixels on an iOS or watchOS device."
   s.description      = <<-DESC
                        IRLSize is used to determine the physical size of the device
@@ -14,18 +14,26 @@ Pod::Spec.new do |s|
   s.source           = { :git => "https://github.com/detroit-labs/IRLSize.git",
                          :tag => s.version.to_s }
 
-  s.ios.deployment_target = '8.0'
-  s.watchos.deployment_target = '2.0'
+  s.ios.deployment_target = '10.0'
+  s.watchos.deployment_target = '3.0'
   s.requires_arc = true
 
   s.source_files = 'Pod/Classes/*', 'Pod/Classes/Private/*'
   s.private_header_files = 'Pod/Classes/Private/*.h'
+  s.frameworks = 'Foundation'
 
   s.ios.source_files = 'Pod/Classes/iOS/*'
-  s.ios.frameworks = 'Foundation', 'UIKit'
+  s.ios.frameworks = 'UIKit'
 
   s.watchos.source_files = 'Pod/Classes/watchOS/*'
-  s.watchos.frameworks = 'Foundation', 'WatchKit'
+  s.watchos.frameworks = 'WatchKit'
 
   s.dependency 'SDVersion', '~> 4.3.0'
+
+  s.test_spec 'IRLSizeTests' do |ts|
+    ts.platform = :ios, '10.0'
+    ts.source_files = 'IRLSizeTests/*.{h,m}'
+    ts.dependency 'Kiwi'
+    ts.requires_app_host = true
+  end
 end
diff --git a/Example/IRLSizeTests/IRLMeasurementBeWithinMatcher.h b/IRLSizeTests/IRLMeasurementBeWithinMatcher.h
similarity index 87%
rename from Example/IRLSizeTests/IRLMeasurementBeWithinMatcher.h
rename to IRLSizeTests/IRLMeasurementBeWithinMatcher.h
index f5cc8a1..445b440 100644
--- a/Example/IRLSizeTests/IRLMeasurementBeWithinMatcher.h
+++ b/IRLSizeTests/IRLMeasurementBeWithinMatcher.h
@@ -3,7 +3,7 @@
 //  IRLSizeExample
 //
 //  Created by Jeff Kelley on 8/13/2016.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import <Kiwi/Kiwi.h>
diff --git a/Example/IRLSizeTests/IRLMeasurementBeWithinMatcher.m b/IRLSizeTests/IRLMeasurementBeWithinMatcher.m
similarity index 96%
rename from Example/IRLSizeTests/IRLMeasurementBeWithinMatcher.m
rename to IRLSizeTests/IRLMeasurementBeWithinMatcher.m
index b295e6f..bdc965c 100644
--- a/Example/IRLSizeTests/IRLMeasurementBeWithinMatcher.m
+++ b/IRLSizeTests/IRLMeasurementBeWithinMatcher.m
@@ -3,7 +3,7 @@
 //  IRLSizeExample
 //
 //  Created by Jeff Kelley on 8/13/2016.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import "IRLMeasurementBeWithinMatcher.h"
diff --git a/Example/IRLSizeTests/IRLSizeTests-Info.plist b/IRLSizeTests/IRLSizeTests-Info.plist
similarity index 100%
rename from Example/IRLSizeTests/IRLSizeTests-Info.plist
rename to IRLSizeTests/IRLSizeTests-Info.plist
diff --git a/IRLSizeTests/IRLSizeTests.m b/IRLSizeTests/IRLSizeTests.m
new file mode 100644
index 0000000..0372485
--- /dev/null
+++ b/IRLSizeTests/IRLSizeTests.m
@@ -0,0 +1,441 @@
+//
+//  IRLSizeTests.m
+//  IRLSizeTests
+//
+//  Created by Jeff Kelley on 11/13/2014.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
+//
+
+#import <IRLSize/IRLSize.h>
+
+#import <UIKit/UIKit.h>
+
+#import <Kiwi/Kiwi.h>
+#import <SDVersion/SDVersion.h>
+
+#import "iOSDeviceConstants.h"
+#import "IRLMeasurementBeWithinMatcher.h"
+
+#define KNOWN_DEVICE_TEST_UNMATCHING(name, modelEnum, sizeEnumPrefix) \
+    context(@"on an " name, ^{ \
+        beforeEach(^{ \
+            [SDiOSVersion stub:@selector(deviceVersion) \
+                     andReturn:theValue(modelEnum)]; \
+        }); \
+        it(@"should report the correct height", ^{ \
+            NSLog(@"Expecting device " #modelEnum " height to equal %f", \
+                  k##sizeEnumPrefix##ScreenHeight); \
+            [[UIDevice.currentDevice.irl_physicalScreenHeight should] \
+             beWithin:0.01 \
+             ofMeasurement:IRL_MM(k##sizeEnumPrefix##ScreenHeight)]; \
+            [[theValue(UIDevice.currentDevice.irl_rawPhysicalScreenHeight) should] \
+             beWithin:theValue(0.1) \
+             of:theValue(k##sizeEnumPrefix##ScreenHeight)]; \
+        }); \
+        it(@"should report the correct width", ^{ \
+            NSLog(@"Expecting device " #modelEnum " width to equal %f", \
+                  k##sizeEnumPrefix##ScreenWidth); \
+            [[UIDevice.currentDevice.irl_physicalScreenWidth should] \
+             beWithin:0.01 \
+             ofMeasurement:IRL_MM(k##sizeEnumPrefix##ScreenWidth)]; \
+            [[theValue(UIDevice.currentDevice.irl_rawPhysicalScreenWidth) should] \
+             beWithin:theValue(0.1) \
+             of:theValue(k##sizeEnumPrefix##ScreenWidth)]; \
+        }); \
+    });
+
+#define KNOWN_DEVICE_TEST_MATCHING(name, enum) \
+    KNOWN_DEVICE_TEST_UNMATCHING(name, enum, enum)
+
+SPEC_BEGIN(IRLSizeTests)
+
+describe(@"Getting the native size of a device", ^{
+
+    registerMatchers(@"IRL");
+
+    KNOWN_DEVICE_TEST_MATCHING("iPhone 5", iPhone5)
+    KNOWN_DEVICE_TEST_UNMATCHING("iPhone 5c", iPhone5C, iPhone5c)
+    KNOWN_DEVICE_TEST_UNMATCHING("iPhone 5s", iPhone5S, iPhone5s)
+    KNOWN_DEVICE_TEST_MATCHING("iPhone SE", iPhoneSE)
+    KNOWN_DEVICE_TEST_MATCHING("iPhone 6", iPhone6)
+    KNOWN_DEVICE_TEST_MATCHING("iPhone 6 Plus", iPhone6Plus)
+    KNOWN_DEVICE_TEST_UNMATCHING("iPhone 6s", iPhone6S, iPhone6s)
+    KNOWN_DEVICE_TEST_UNMATCHING("iPhone 6s Plus", iPhone6SPlus, iPhone6sPlus)
+    KNOWN_DEVICE_TEST_MATCHING("iPhone 7", iPhone7)
+    KNOWN_DEVICE_TEST_MATCHING("iPhone 7 Plus", iPhone7Plus)
+    KNOWN_DEVICE_TEST_MATCHING("iPhone 8", iPhone8)
+    KNOWN_DEVICE_TEST_MATCHING("iPhone 8 Plus", iPhone8Plus)
+    KNOWN_DEVICE_TEST_MATCHING("iPhone X", iPhoneX)
+
+    KNOWN_DEVICE_TEST_MATCHING("iPad (4th Generation)", iPad4)
+    KNOWN_DEVICE_TEST_MATCHING("iPad mini", iPadMini)
+    KNOWN_DEVICE_TEST_MATCHING("iPad Air", iPadAir)
+    KNOWN_DEVICE_TEST_MATCHING("iPad mini (2nd Generation)", iPadMini2)
+    KNOWN_DEVICE_TEST_MATCHING("iPad Air2", iPadAir2)
+    KNOWN_DEVICE_TEST_MATCHING("iPad mini (3rd Generation)", iPadMini3)
+    KNOWN_DEVICE_TEST_UNMATCHING("iPad Pro (9.7\")", iPadPro9Dot7Inch, iPadPro9_7Inch)
+    KNOWN_DEVICE_TEST_UNMATCHING("iPad Pro (12.9\")", iPadPro12Dot9Inch, iPadPro12_9Inch)
+    KNOWN_DEVICE_TEST_MATCHING("iPad mini (4th Generation)", iPadMini4)
+    KNOWN_DEVICE_TEST_MATCHING("iPad (5th Generation)", iPad5)
+    KNOWN_DEVICE_TEST_UNMATCHING("iPad Pro (10.5\")", iPadPro10Dot5Inch, iPadPro10_5Inch)
+    KNOWN_DEVICE_TEST_UNMATCHING("iPad Pro (12.9\", 2nd Generation)", iPadPro12Dot9Inch2Gen, iPadPro12_9Inch2)
+
+    KNOWN_DEVICE_TEST_UNMATCHING("iPod touch (5th Generation)", iPodTouch5Gen, iPodTouch5)
+    KNOWN_DEVICE_TEST_UNMATCHING("iPod touch (6th Generation)", iPodTouch6Gen, iPodTouch6)
+
+});
+
+#define ESTIMATED_SIZE_TEST(width, height, deviceScale, size, deviceType) \
+    context(@"On a device with a resolution of " #width " ⨉ " #height " at " #deviceScale "x", ^{ \
+        beforeEach(^{ \
+            [mockCoordinateSpace stub:@selector(bounds) \
+                            andReturn:theValue(CGRectMake(0.0f, 0.0f, \
+                                                          width##.0f, height##.0f))]; \
+            [mockScreen stub:@selector(scale) andReturn:theValue(deviceScale##.0f)]; \
+        }); \
+        it(@"should estimate the size of a " #size " Inch " #deviceType, ^{ \
+            NSLog(@"Expecting screen size " #width "⨉" #height " and scale " \
+                  #deviceScale " to equal " #size " inches"); \
+            [[UIDevice.currentDevice.irl_physicalScreenHeight should] \
+             beWithin:0.01 \
+             ofMeasurement:IRL_MM(k##deviceType##size##InchScreenHeight)]; \
+            [[UIDevice.currentDevice.irl_physicalScreenWidth should] \
+             beWithin:0.01 \
+             ofMeasurement:IRL_MM(k##deviceType##size##InchScreenWidth)]; \
+        }); \
+    });
+
+describe(@"Estimating the size of an unknown device based on the screen size", ^{
+    
+    registerMatchers(@"IRL");
+    
+    __block UIScreen *mockScreen = nil;
+    __block NSObject <UICoordinateSpace> *mockCoordinateSpace = nil;
+    
+    beforeEach(^{
+        
+        [SDiOSVersion stub:@selector(deviceVersion)
+                 andReturn:theValue(Simulator)];
+        
+        mockScreen = [UIScreen mock];
+        mockCoordinateSpace = [KWMock mockForProtocol:@protocol(UICoordinateSpace)];
+        
+        [UIScreen stub:@selector(mainScreen) andReturn:mockScreen];
+        
+        [mockScreen stub:@selector(fixedCoordinateSpace)
+               andReturn:mockCoordinateSpace];
+        
+    });
+    
+    afterEach(^{
+        
+        mockScreen = nil;
+        
+    });
+
+    ESTIMATED_SIZE_TEST(320, 480, 1, 3_5, iPhone)
+    ESTIMATED_SIZE_TEST(320, 480, 2, 3_5, iPhone)
+    ESTIMATED_SIZE_TEST(320, 568, 2, 4_0, iPhone)
+    ESTIMATED_SIZE_TEST(375, 667, 2, 4_7, iPhone)
+    ESTIMATED_SIZE_TEST(414, 736, 3, 5_5, iPhone)
+    ESTIMATED_SIZE_TEST(375, 812, 3, 5_8, iPhone)
+    ESTIMATED_SIZE_TEST(414, 896, 2, 6_1, iPhone)
+    ESTIMATED_SIZE_TEST(414, 896, 3, 6_5, iPhone)
+
+    ESTIMATED_SIZE_TEST(768,  1024, 1,  9_7, iPad)
+    ESTIMATED_SIZE_TEST(768,  1024, 2,  9_7, iPad)
+    ESTIMATED_SIZE_TEST(834,  1112, 2, 10_5, iPad)
+    ESTIMATED_SIZE_TEST(1024, 1366, 2, 12_9, iPad)
+    
+});
+
+describe(@"Getting the IRL size of a view", ^{
+    
+    registerMatchers(@"IRL");
+    
+    __block UIApplication *mockSharedApplication;
+    __block UIScreen *mockMainScreen;
+    __block UIWindow *mockWindow;
+    
+    beforeEach(^{
+        
+        mockMainScreen = [UIScreen mock];
+        
+        [UIScreen stub:@selector(mainScreen)
+             andReturn:mockMainScreen];
+        
+        mockWindow = [UIWindow mock];
+        
+        [mockWindow stub:@selector(screen)
+               andReturn:mockMainScreen];
+        
+        mockSharedApplication = [UIApplication mock];
+        
+        [mockSharedApplication stub:@selector(statusBarOrientation)
+                          andReturn:theValue(UIInterfaceOrientationPortrait)];
+        
+        [mockSharedApplication stub:@selector(keyWindow)
+                          andReturn:mockWindow];
+        
+        [UIApplication stub:@selector(sharedApplication)
+                  andReturn:mockSharedApplication];
+        
+        [mockWindow stub:@selector(convertRect:fromView:)
+               withBlock:^id(NSArray *params) {
+                   NSValue *frameValue = params[0];
+                   
+                   CGRect frame = [frameValue CGRectValue];
+                   
+                   return theValue(frame);
+               }];
+        
+    });
+    
+    context(@"on an iPhone 6s", ^{
+        
+        __block UIView *view;
+        
+        beforeEach(^{
+            
+            CGRect iPhone6sBounds = CGRectMake(0.0f, 0.0f,
+                                               375.0f, 667.0f);
+            
+            KWMock <UICoordinateSpace> *mockFixedCoordinateSpace =
+            [KWMock mockForProtocol:@protocol(UICoordinateSpace)];
+            
+            [mockFixedCoordinateSpace stub:@selector(bounds)
+                                 andReturn:theValue(iPhone6sBounds)];
+            
+            [mockMainScreen stub:@selector(fixedCoordinateSpace)
+                       andReturn:mockFixedCoordinateSpace];
+            
+            [mockMainScreen stub:@selector(bounds)
+                       andReturn:theValue(iPhone6sBounds)];
+            
+            [SDiOSVersion stub:@selector(deviceVersion)
+                     andReturn:theValue(iPhone6S)];
+            
+            [mockWindow stub:@selector(bounds)
+                   andReturn:theValue(iPhone6sBounds)];
+            
+            view = [[UIView alloc] initWithFrame:CGRectMake(0.0f,
+                                                            0.0f,
+                                                            100.0f,
+                                                            100.0f)];
+            
+        });
+        
+        context(@"when a view is on the main screen", ^{
+            
+            beforeEach(^{
+                
+                [view stub:@selector(window) andReturn:mockWindow];
+                [view stub:@selector(superview) andReturn:mockWindow];
+                
+            });
+            
+            it(@"should report the correct size", ^{
+                
+                NSMeasurement<NSUnitLength *> *expectedSize =
+                [[NSMeasurement alloc] initWithDoubleValue:0.01654589372
+                                                      unit:[NSUnitLength meters]];
+                
+                [[view.irl_physicalWidth should] beWithin:0.01
+                                            ofMeasurement:expectedSize];
+                
+                [[view.irl_physicalHeight should] beWithin:0.01
+                                             ofMeasurement:expectedSize];
+                
+            });
+            
+            it(@"should return the correct transform to resize the view", ^{
+                
+                CGAffineTransform transform =
+                [view irl_transformForPhysicalWidth:
+                 [[NSMeasurement alloc] initWithDoubleValue:0.01
+                                                       unit:[NSUnitLength meters]]];
+                
+                CGAffineTransform expectedTransform =
+                CGAffineTransformMakeScale(0.641025602, 0.641025602);
+                
+                [[theValue(transform.a) should] equal:expectedTransform.a
+                                            withDelta:0.001];
+                
+                [[theValue(transform.d) should] equal:expectedTransform.d
+                                            withDelta:0.001];
+                
+            });
+            
+        });
+        
+        context(@"when a view is not attached to a window", ^{
+            
+            it(@"should report the correct size", ^{
+                
+                NSMeasurement<NSUnitLength *> *expectedSize =
+                [[NSMeasurement alloc] initWithDoubleValue:0.01654589372
+                                                      unit:[NSUnitLength meters]];
+                
+                [[view.irl_physicalWidth should] beWithin:0.01
+                                            ofMeasurement:expectedSize];
+                
+                [[view.irl_physicalHeight should] beWithin:0.01
+                                             ofMeasurement:expectedSize];
+                
+            });
+            
+            it(@"should return the correct transform to resize the view", ^{
+                
+                CGAffineTransform transform =
+                [view irl_transformForPhysicalWidth:
+                 [[NSMeasurement alloc] initWithDoubleValue:0.01f
+                                                       unit:[NSUnitLength meters]]];
+                
+                CGAffineTransform expectedTransform =
+                CGAffineTransformMakeScale(0.641025602, 0.641025602);
+                
+                [[theValue(transform.a) should] equal:expectedTransform.a
+                                            withDelta:0.001];
+                
+                [[theValue(transform.d) should] equal:expectedTransform.d
+                                            withDelta:0.001];
+                
+            });
+            
+        });
+        
+        context(@"when there is no key window", ^{
+            
+            beforeEach(^{
+                
+                [UIApplication.sharedApplication stub:@selector(keyWindow)
+                                            andReturn:nil];
+                
+            });
+            
+            it(@"should report the correct size", ^{
+                
+                NSMeasurement<NSUnitLength *> *expectedSize =
+                [[NSMeasurement alloc] initWithDoubleValue:0.01654589372
+                                                      unit:[NSUnitLength meters]];
+                
+                [[view.irl_physicalWidth should] beWithin:0.01
+                                            ofMeasurement:expectedSize];
+                
+                [[view.irl_physicalHeight should] beWithin:0.01
+                                             ofMeasurement:expectedSize];
+                
+            });
+            
+            it(@"should return the correct transform to resize the view", ^{
+                
+                CGAffineTransform transform =
+                [view irl_transformForPhysicalWidth:
+                 [[NSMeasurement alloc] initWithDoubleValue:0.01
+                                                       unit:[NSUnitLength meters]]];
+                
+                CGAffineTransform expectedTransform =
+                CGAffineTransformMakeScale(0.641025602, 0.641025602);
+                
+                [[theValue(transform.a) should] equal:expectedTransform.a
+                                            withDelta:0.001];
+                
+                [[theValue(transform.d) should] equal:expectedTransform.d
+                                            withDelta:0.001];
+                
+            });
+            
+            context(@"when the device is rotated to landscape", ^{
+                
+                beforeEach(^{
+                    
+                    [mockSharedApplication stub:@selector(statusBarOrientation)
+                                      andReturn:theValue(UIInterfaceOrientationLandscapeLeft)];
+                    
+                });
+                
+                it(@"should report the correct size", ^{
+                    
+                    NSMeasurement<NSUnitLength *> *expectedSize =
+                    [[NSMeasurement alloc] initWithDoubleValue:0.01654589372
+                                                          unit:[NSUnitLength meters]];
+                    
+                    [[view.irl_physicalWidth should] beWithin:0.01
+                                                ofMeasurement:expectedSize];
+                    
+                    [[view.irl_physicalHeight should] beWithin:0.01
+                                                 ofMeasurement:expectedSize];
+                    
+                    
+                });
+                
+                it(@"should return the correct transform to resize the view", ^{
+                    
+                    CGAffineTransform transform =
+                    [view irl_transformForPhysicalWidth:
+                     [[NSMeasurement alloc] initWithDoubleValue:0.01
+                                                           unit:[NSUnitLength meters]]];
+                    
+                    CGAffineTransform expectedTransform =
+                    CGAffineTransformMakeScale(0.641025602, 0.641025602);
+                    
+                    [[theValue(transform.a) should] equal:expectedTransform.a
+                                                withDelta:0.001];
+                    
+                    [[theValue(transform.d) should] equal:expectedTransform.d
+                                                withDelta:0.001];
+                    
+                });
+                
+            });
+            
+        });
+        
+        context(@"when a view is on a secondary screen", ^{
+            
+            beforeEach(^{
+                
+                UIScreen *mockOtherScreen = [UIScreen mock];
+                UIWindow *mockOtherWindow = [UIWindow mock];
+                
+                [mockOtherWindow stub:@selector(screen)
+                            andReturn:mockOtherScreen];
+                
+                [view stub:@selector(superview)
+                 andReturn:mockOtherWindow];
+                
+                [view stub:@selector(window)
+                 andReturn:mockOtherWindow];
+                
+                [view stub:@selector(transform)
+                 andReturn:theValue(CGAffineTransformIdentity)];
+                
+            });
+            
+            it(@"should not return a size", ^{
+                
+                [[view.irl_physicalWidth should] beNil];
+                [[view.irl_physicalHeight should] beNil];
+                
+            });
+            
+            it(@"should reuse the view’s transform for resizing", ^{
+                
+                NSMeasurement<NSUnitLength *> *desiredWidth =
+                [[NSMeasurement alloc] initWithDoubleValue:0.42
+                                                      unit:[NSUnitLength meters]];
+                
+                CGAffineTransform transform =
+                [view irl_transformForPhysicalWidth:desiredWidth];
+                
+                [[theValue(CGAffineTransformIsIdentity(transform)) should] beTrue];
+                
+            });
+            
+        });
+        
+    });
+    
+});
+
+SPEC_END
diff --git a/Example/IRLSizeTests/NSMeasurement+Equality.h b/IRLSizeTests/NSMeasurement+Equality.h
similarity index 93%
rename from Example/IRLSizeTests/NSMeasurement+Equality.h
rename to IRLSizeTests/NSMeasurement+Equality.h
index 394144e..1953ffb 100644
--- a/Example/IRLSizeTests/NSMeasurement+Equality.h
+++ b/IRLSizeTests/NSMeasurement+Equality.h
@@ -3,7 +3,7 @@
 //  IRLSizeExample
 //
 //  Created by Jeff Kelley on 8/13/16.
-//  Copyright © 2016 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import <Foundation/Foundation.h>
diff --git a/Example/IRLSizeTests/NSMeasurement+Equality.m b/IRLSizeTests/NSMeasurement+Equality.m
similarity index 90%
rename from Example/IRLSizeTests/NSMeasurement+Equality.m
rename to IRLSizeTests/NSMeasurement+Equality.m
index cd8f8d3..deff1f2 100644
--- a/Example/IRLSizeTests/NSMeasurement+Equality.m
+++ b/IRLSizeTests/NSMeasurement+Equality.m
@@ -3,7 +3,7 @@
 //  IRLSizeExample
 //
 //  Created by Jeff Kelley on 8/13/16.
-//  Copyright © 2016 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import "NSMeasurement+Equality.h"
diff --git a/Example/IRLSizeTests/en.lproj/InfoPlist.strings b/IRLSizeTests/en.lproj/InfoPlist.strings
similarity index 100%
rename from Example/IRLSizeTests/en.lproj/InfoPlist.strings
rename to IRLSizeTests/en.lproj/InfoPlist.strings
diff --git a/LICENSE b/LICENSE
index a423318..c4489d5 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,4 +1,4 @@
-Copyright (c) 2017 Detroit Labs
+Copyright (c) 2018 Detroit Labs
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/Pod/Classes/IRLSize.h b/Pod/Classes/IRLSize.h
index e860825..5135573 100644
--- a/Pod/Classes/IRLSize.h
+++ b/Pod/Classes/IRLSize.h
@@ -3,27 +3,20 @@
 //  IRLSize
 //
 //  Created by Jeff Kelley on 11/13/2014.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import <TargetConditionals.h>
 
-#define IRL_SUPPORTS_NSMEASUREMENT (__IPHONE_10_0 > 0 && __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_10_0)
-
-#if TARGET_OS_IOS
-    #define IRL_IOS_AVAILABLE(v) __attribute__((availability(ios,introduced=v)))
-#elif TARGET_OS_WATCH
-    #define IRL_WATCHOS_AVAILABLE(v) __attribute__((availability(watchos,introduced=v)))
-#endif
-
-typedef float IRLRawLengthMeasurement; // meters
+typedef double IRLRawMillimeters;
 
 typedef struct {
-    IRLRawLengthMeasurement width;
-    IRLRawLengthMeasurement height;
-} IRLRawSize;
+    IRLRawMillimeters width;
+    IRLRawMillimeters height;
+} IRLRawDimensions;
 
-#define IRL_RAW_SIZE_UNIT NSUnitLength.meters
+#define IRL_SIZE_UNIT NSUnitLength.millimeters
+#define IRL_MM(x) [[NSMeasurement alloc] initWithDoubleValue:(x) unit: IRL_SIZE_UNIT]
 
 #if TARGET_OS_IOS
     #import "UIDevice+IRLSize.h"
diff --git a/Pod/Classes/Private/UIDevice+IRLSizePrivate.h b/Pod/Classes/Private/UIDevice+IRLSizePrivate.h
index 466267f..97b886a 100644
--- a/Pod/Classes/Private/UIDevice+IRLSizePrivate.h
+++ b/Pod/Classes/Private/UIDevice+IRLSizePrivate.h
@@ -3,7 +3,7 @@
 //  IRLSize
 //
 //  Created by Jeff Kelley on 6/29/2016.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import <UIKit/UIKit.h>
@@ -13,7 +13,7 @@
 #if TARGET_OS_IOS
 @interface UIDevice (IRLSizePrivate)
 
-- (IRLRawSize)irl_rawPhysicalSizeOfView:(nonnull UIView *)view;
+- (IRLRawDimensions)irl_rawPhysicalSizeOfView:(nonnull UIView *)view;
 
 @end
 #endif
diff --git a/Pod/Classes/Private/UIView+IRLSizePrivate.h b/Pod/Classes/Private/UIView+IRLSizePrivate.h
index 38c5e10..989980d 100644
--- a/Pod/Classes/Private/UIView+IRLSizePrivate.h
+++ b/Pod/Classes/Private/UIView+IRLSizePrivate.h
@@ -3,7 +3,7 @@
 //  IRLSize
 //
 //  Created by Jeff Kelley on 7/6/2016.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import <UIKit/UIKit.h>
diff --git a/Pod/Classes/iOS/UIDevice+IRLSize.h b/Pod/Classes/iOS/UIDevice+IRLSize.h
index 24c4cf3..b9ecde4 100644
--- a/Pod/Classes/iOS/UIDevice+IRLSize.h
+++ b/Pod/Classes/iOS/UIDevice+IRLSize.h
@@ -3,7 +3,7 @@
 //  IRLSize
 //
 //  Created by Jeff Kelley on 11/13/2014.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import <UIKit/UIKit.h>
@@ -14,29 +14,25 @@ NS_ASSUME_NONNULL_BEGIN
 
 @interface UIDevice (IRLSize)
 
-#if IRL_SUPPORTS_NSMEASUREMENT
 /**
  The physical height of the device’s screen.
  */
-@property (nonatomic, readonly) NSMeasurement<NSUnitLength *> *irl_physicalScreenHeight NS_SWIFT_NAME(physicalScreenHeight) IRL_IOS_AVAILABLE(10.0);
-#endif
+@property (nonatomic, readonly) NSMeasurement<NSUnitLength *> *irl_physicalScreenHeight NS_SWIFT_NAME(physicalScreenHeight);
 
 /**
  The physical height of the device’s screen as a raw value.
  */
-@property (nonatomic, readonly) IRLRawLengthMeasurement irl_rawPhysicalScreenHeight NS_SWIFT_NAME(rawPhysicalScreenHeight);
+@property (nonatomic, readonly) IRLRawMillimeters irl_rawPhysicalScreenHeight NS_SWIFT_NAME(rawPhysicalScreenHeight);
 
-#if IRL_SUPPORTS_NSMEASUREMENT
 /**
  The physical width of the device’s screen.
  */
-@property (nonatomic, readonly) NSMeasurement<NSUnitLength *> *irl_physicalScreenWidth NS_SWIFT_NAME(physicalScreenWidth) IRL_IOS_AVAILABLE(10.0);
-#endif
+@property (nonatomic, readonly) NSMeasurement<NSUnitLength *> *irl_physicalScreenWidth NS_SWIFT_NAME(physicalScreenWidth);
 
 /**
  The physical width of the device’s screen as a raw value.
  */
-@property (nonatomic, readonly) IRLRawLengthMeasurement irl_rawPhysicalScreenWidth NS_SWIFT_NAME(rawPhysicalScreenWidth);
+@property (nonatomic, readonly) IRLRawMillimeters irl_rawPhysicalScreenWidth NS_SWIFT_NAME(rawPhysicalScreenWidth);
 
 @end
 
diff --git a/Pod/Classes/iOS/UIDevice+IRLSize.m b/Pod/Classes/iOS/UIDevice+IRLSize.m
index e7045f1..7076907 100644
--- a/Pod/Classes/iOS/UIDevice+IRLSize.m
+++ b/Pod/Classes/iOS/UIDevice+IRLSize.m
@@ -3,7 +3,7 @@
 //  IRLSize
 //
 //  Created by Jeff Kelley on 11/13/2014.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import "IRLSize.h"
@@ -11,54 +11,19 @@
 #import <SDVersion/SDVersion.h>
 
 #import "UIView+IRLSizePrivate.h"
+#import "iOSDeviceConstants.h"
 
-// https://www.sven.de/dpi/ is a good resource for determining screen sizes.
-
-// iPhone/iPod touch
-static const float kiPhone3_5InchScreenHeight = 0.0740f;
-static const float kiPhone3_5InchScreenWidth = 0.0493f;
-static const float kiPhone4_0InchScreenHeight = 0.0885f;
-static const float kiPhone4_0InchScreenWidth = 0.0499f;
-static const float kiPhone4_7InchScreenHeight = 0.1041f;
-static const float kiPhone4_7InchScreenWidth = 0.0585f;
-static const float kiPhone5_5InchScreenHeight = 0.1218f;
-static const float kiPhone5_5InchScreenWidth = 0.0685f;
-static const float kiPhone5_8InchScreenHeight = 0.1337f;
-static const float kiPhone5_8InchScreenWidth = 0.0618f;
-static const float kiPhone6_1InchScreenHeight = 0.1407f;
-static const float kiPhone6_1InchScreenWidth = 0.065f;
-static const float kiPhone6_5InchScreenHeight = 0.1499f;
-static const float kiPhone6_5InchScreenWidth = 0.0693f;
-
-static const NSUInteger kiPhone3_5InchHeightPoints = 480;
-static const NSUInteger kiPhone4_0InchHeightPoints = 568;
-static const NSUInteger kiPhone4_7InchHeightPoints = 667;
-static const NSUInteger kiPhone5_5InchHeightPoints = 736;
-static const NSUInteger kiPhone5_8InchHeightPoints = 812;
-// The 6.1" and 6.5" phones both have 896 height points, so we'll need to use
-// different techniques to identify them.
-static const NSUInteger kiPhone6_1InchHeightPoints = 896;
-
-// iPad
-static const float kiPad7_9InchScreenHeight = 0.1605f;
-static const float kiPad7_9InchScreenWidth = 0.1204f;
-static const float kiPad9_7InchScreenHeight = 0.1971f;
-static const float kiPad9_7InchScreenWidth = 0.1478f;
-static const float kiPad10_5InchScreenHeight = 0.2134f;
-static const float kiPad10_5InchScreenWidth = 0.16f;
-static const float kiPad12_9InchScreenHeight = 0.2622f;
-static const float kiPad12_9InchScreenWidth = 0.1965f;
-
-static const NSUInteger kiPadHeightPoints = 1024;
-static const NSUInteger kiPadPro10Dot5InchHeightPoints = 1112;
-static const NSUInteger kiPadPro12Dot9InchHeightPoints = 1366;
-
+void IRLRawDimensionsSwap(IRLRawDimensions *dimensions) {
+    IRLRawMillimeters temp = dimensions->width;
+    dimensions->width = dimensions->height;
+    dimensions->height = temp;
+}
 
 @implementation UIDevice (IRLSizePrivate)
 
-- (IRLRawSize)irl_rawPhysicalSizeOfView:(UIView *)view
+- (IRLRawDimensions)irl_rawPhysicalSizeOfView:(UIView *)view
 {
-    IRLRawSize dimensions = { 0.0f, 0.0f };
+    IRLRawDimensions dimensions = { 0.0f, 0.0f };
     
     // If the view’s window is nil, we’ll just assume that it will be going onto
     // the main screen. This is what happens if you use this code during
@@ -81,17 +46,15 @@ - (IRLRawSize)irl_rawPhysicalSizeOfView:(UIView *)view
         
         CGSize windowSize = window.screen.bounds.size;
         
+        IRLRawDimensions rawPhysicalScreenSize = [self irl_rawPhysicalScreenSize];
+        
         if (window == nil) {
             windowSize = UIScreen.mainScreen.fixedCoordinateSpace.bounds.size;
         }
         else if (UIInterfaceOrientationIsLandscape(application.statusBarOrientation)) {
-            CGSize windowSizeSwap = CGSizeMake(windowSize.height,
-                                               windowSize.width);
-            windowSize = windowSizeSwap;
+            IRLRawDimensionsSwap(&rawPhysicalScreenSize);
         }
         
-        IRLRawSize rawPhysicalScreenSize = [self irl_rawPhysicalScreenSize];
-        
         dimensions.width = ((CGRectGetWidth(convertedFrame) / windowSize.width) *
                             rawPhysicalScreenSize.width);
         
@@ -102,10 +65,17 @@ - (IRLRawSize)irl_rawPhysicalSizeOfView:(UIView *)view
     return dimensions;
 }
 
-- (IRLRawSize)irl_estimatedRawPhysicalScreenSizeFromScreenPointHeight
-{
-    IRLRawSize estimatedDimensions = { 0.0f, 0.0f };
+#define IRL_ESTIMATED_DIMENSIONS(variable, deviceType, size) \
+    case k##deviceType##size##InchHeightPoints: { \
+        variable.height = k##deviceType##size##InchScreenHeight; \
+        variable.width = k##deviceType##size##InchScreenWidth; \
+    } \
+    break;
 
+- (IRLRawDimensions)irl_estimatedRawPhysicalScreenSizeFromScreenPointHeight
+{
+    IRLRawDimensions estimatedDimensions = { 0.0f, 0.0f };
+    
     UIScreen *mainScreen = UIScreen.mainScreen;
     CGRect portraitBounds = mainScreen.fixedCoordinateSpace.bounds;
     
@@ -113,132 +83,76 @@ - (IRLRawSize)irl_estimatedRawPhysicalScreenSizeFromScreenPointHeight
     NSUInteger scale = mainScreen.scale;
     
     switch (heightPoints) {
-        case kiPhone3_5InchHeightPoints:
-            estimatedDimensions.width = kiPhone3_5InchScreenWidth;
-            estimatedDimensions.height = kiPhone3_5InchScreenHeight;
-            break;
-            
-        case kiPhone4_0InchHeightPoints:
-            estimatedDimensions.width = kiPhone4_0InchScreenWidth;
-            estimatedDimensions.height = kiPhone4_0InchScreenHeight;
-            break;
-            
-        case kiPhone4_7InchHeightPoints:
-            estimatedDimensions.width = kiPhone4_7InchScreenWidth;
-            estimatedDimensions.height = kiPhone4_7InchScreenHeight;
-            break;
+            IRL_ESTIMATED_DIMENSIONS(estimatedDimensions, iPhone, 3_5)
+            IRL_ESTIMATED_DIMENSIONS(estimatedDimensions, iPhone, 4_0)
+            IRL_ESTIMATED_DIMENSIONS(estimatedDimensions, iPhone, 4_7)
+            IRL_ESTIMATED_DIMENSIONS(estimatedDimensions, iPhone, 5_5)
+            IRL_ESTIMATED_DIMENSIONS(estimatedDimensions, iPhone, 5_8)
             
-        case kiPhone5_5InchHeightPoints:
-            estimatedDimensions.width = kiPhone5_5InchScreenWidth;
-            estimatedDimensions.height = kiPhone5_5InchScreenHeight;
-            break;
-            
-        case kiPhone5_8InchHeightPoints:
-            estimatedDimensions.width = kiPhone5_8InchScreenWidth;
-            estimatedDimensions.height = kiPhone5_8InchScreenHeight;
-            break;
-
         case kiPhone6_1InchHeightPoints:
             if (scale == 3) {
-                estimatedDimensions.width = kiPhone6_5InchScreenWidth;
                 estimatedDimensions.height = kiPhone6_5InchScreenHeight;
+                estimatedDimensions.width = kiPhone6_5InchScreenWidth;
             }
             else {
-                estimatedDimensions.width = kiPhone6_1InchScreenWidth;
                 estimatedDimensions.height = kiPhone6_1InchScreenHeight;
+                estimatedDimensions.width = kiPhone6_1InchScreenWidth;
             }
             break;
             
-        case kiPadHeightPoints:
-            estimatedDimensions.width = kiPad9_7InchScreenWidth;
-            estimatedDimensions.height = kiPad9_7InchScreenHeight;
-            break;
-            
-        case kiPadPro10Dot5InchHeightPoints:
-            estimatedDimensions.width = kiPad10_5InchScreenWidth;
-            estimatedDimensions.height = kiPad10_5InchScreenHeight;
-            break;
-            
-        case kiPadPro12Dot9InchHeightPoints:
-            estimatedDimensions.width = kiPad12_9InchScreenWidth;
-            estimatedDimensions.height = kiPad12_9InchScreenHeight;
-            break;
+            IRL_ESTIMATED_DIMENSIONS(estimatedDimensions, iPad, 9_7)
+            IRL_ESTIMATED_DIMENSIONS(estimatedDimensions, iPadPro, 10_5)
+            IRL_ESTIMATED_DIMENSIONS(estimatedDimensions, iPadPro, 12_9)
     }
     
     return estimatedDimensions;
 }
 
-- (IRLRawSize)irl_rawPhysicalScreenSize
+#define IRL_KNOWN_DEVICE_DIMENSIONS_UNMATCHING(modelEnum, sizeEnumPrefix)\
+    case modelEnum: { \
+        size.height = k##sizeEnumPrefix##ScreenHeight; \
+        size.width = k##sizeEnumPrefix##ScreenWidth; \
+    } \
+    break;
+
+#define IRL_KNOWN_DEVICE_DIMENSIONS_MATCHING(enum) \
+    IRL_KNOWN_DEVICE_DIMENSIONS_UNMATCHING(enum, enum)
+
+- (IRLRawDimensions)irl_rawPhysicalScreenSize
 {
-    IRLRawSize size = { 0.0f, 0.0f };
+    IRLRawDimensions size = { 0.0f, 0.0f };
     
     switch ([SDiOSVersion deviceVersion]) {
-        case iPhone4S:
-            size.width = kiPhone3_5InchScreenWidth;
-            size.height = kiPhone3_5InchScreenHeight;
-            break;
-            
-        case iPhone5:
-        case iPhone5S:
-        case iPhone5C:
-        case iPhoneSE:
-        case iPodTouch5Gen:
-        case iPodTouch6Gen:
-            size.width = kiPhone4_0InchScreenWidth;
-            size.height = kiPhone4_0InchScreenHeight;
-            break;
-            
-        case iPhone6:
-        case iPhone6S:
-        case iPhone7:
-        case iPhone8:
-            size.width = kiPhone4_7InchScreenWidth;
-            size.height = kiPhone4_7InchScreenHeight;
-            break;
-            
-        case iPhone6Plus:
-        case iPhone6SPlus:
-        case iPhone7Plus:
-        case iPhone8Plus:
-            size.width = kiPhone5_5InchScreenWidth;
-            size.height = kiPhone5_5InchScreenHeight;
-            break;
-            
-        case iPhoneX:
-            size.width = kiPhone5_8InchScreenWidth;
-            size.height = kiPhone5_8InchScreenHeight;
-            break;
-            
-        case iPad2:
-        case iPad3:
-        case iPad4:
-        case iPadAir:
-        case iPadAir2:
-        case iPadPro9Dot7Inch:
-        case iPad5:
-            size.width = kiPad9_7InchScreenWidth;
-            size.height = kiPad9_7InchScreenHeight;
-            break;
-            
-        case iPadMini:
-        case iPadMini2:
-        case iPadMini3:
-        case iPadMini4:
-            size.width = kiPad7_9InchScreenWidth;
-            size.height = kiPad7_9InchScreenHeight;
-            break;
-            
-        case iPadPro10Dot5Inch:
-            size.width = kiPad10_5InchScreenWidth;
-            size.height = kiPad10_5InchScreenHeight;
-            break;
-            
-        case iPadPro12Dot9Inch:
-        case iPadPro12Dot9Inch2Gen:
-            size.width = kiPad12_9InchScreenWidth;
-            size.height = kiPad12_9InchScreenHeight;
-            break;
-            
+            IRL_KNOWN_DEVICE_DIMENSIONS_MATCHING(iPhone5)
+            IRL_KNOWN_DEVICE_DIMENSIONS_UNMATCHING(iPhone5S, iPhone5s)
+            IRL_KNOWN_DEVICE_DIMENSIONS_UNMATCHING(iPhone5C, iPhone5c)
+            IRL_KNOWN_DEVICE_DIMENSIONS_MATCHING(iPhoneSE)
+            IRL_KNOWN_DEVICE_DIMENSIONS_MATCHING(iPhone6)
+            IRL_KNOWN_DEVICE_DIMENSIONS_MATCHING(iPhone6Plus)
+            IRL_KNOWN_DEVICE_DIMENSIONS_UNMATCHING(iPhone6S, iPhone6s)
+            IRL_KNOWN_DEVICE_DIMENSIONS_UNMATCHING(iPhone6SPlus, iPhone6sPlus)
+            IRL_KNOWN_DEVICE_DIMENSIONS_MATCHING(iPhone7)
+            IRL_KNOWN_DEVICE_DIMENSIONS_MATCHING(iPhone7Plus)
+            IRL_KNOWN_DEVICE_DIMENSIONS_MATCHING(iPhone8)
+            IRL_KNOWN_DEVICE_DIMENSIONS_MATCHING(iPhone8Plus)
+            IRL_KNOWN_DEVICE_DIMENSIONS_MATCHING(iPhoneX)
+            
+            IRL_KNOWN_DEVICE_DIMENSIONS_MATCHING(iPad4)
+            IRL_KNOWN_DEVICE_DIMENSIONS_MATCHING(iPadMini)
+            IRL_KNOWN_DEVICE_DIMENSIONS_MATCHING(iPadAir)
+            IRL_KNOWN_DEVICE_DIMENSIONS_MATCHING(iPadMini2)
+            IRL_KNOWN_DEVICE_DIMENSIONS_MATCHING(iPadMini3)
+            IRL_KNOWN_DEVICE_DIMENSIONS_MATCHING(iPadAir2)
+            IRL_KNOWN_DEVICE_DIMENSIONS_MATCHING(iPadMini4)
+            IRL_KNOWN_DEVICE_DIMENSIONS_UNMATCHING(iPadPro9Dot7Inch, iPadPro9_7Inch)
+            IRL_KNOWN_DEVICE_DIMENSIONS_UNMATCHING(iPadPro12Dot9Inch, iPadPro12_9Inch)
+            IRL_KNOWN_DEVICE_DIMENSIONS_MATCHING(iPad5)
+            IRL_KNOWN_DEVICE_DIMENSIONS_UNMATCHING(iPadPro10Dot5Inch, iPadPro10_5Inch)
+            IRL_KNOWN_DEVICE_DIMENSIONS_UNMATCHING(iPadPro12Dot9Inch2Gen, iPadPro12_9Inch2)
+            
+            IRL_KNOWN_DEVICE_DIMENSIONS_UNMATCHING(iPodTouch5Gen, iPodTouch5)
+            IRL_KNOWN_DEVICE_DIMENSIONS_UNMATCHING(iPodTouch6Gen, iPodTouch6)
+
         default:
             size = [self irl_estimatedRawPhysicalScreenSizeFromScreenPointHeight];
             break;
@@ -251,32 +165,24 @@ - (IRLRawSize)irl_rawPhysicalScreenSize
 
 @implementation UIDevice (IRLSize)
 
-#if IRL_SUPPORTS_NSMEASUREMENT
 - (NSMeasurement<NSUnitLength *> *)irl_physicalScreenHeight
 {
-    IRLRawSize deviceDimensions = [self irl_rawPhysicalScreenSize];
-    
-    return [[NSMeasurement alloc] initWithDoubleValue:deviceDimensions.height
-                                                 unit:IRL_RAW_SIZE_UNIT];
+    return IRL_MM(self.irl_rawPhysicalScreenSize.height);
 }
 
 - (NSMeasurement<NSUnitLength *> *)irl_physicalScreenWidth
 {
-    IRLRawSize deviceDimensions = [self irl_rawPhysicalScreenSize];
-    
-    return [[NSMeasurement alloc] initWithDoubleValue:deviceDimensions.width
-                                                 unit:IRL_RAW_SIZE_UNIT];
+    return IRL_MM(self.irl_rawPhysicalScreenSize.width);
 }
-#endif
 
-- (IRLRawLengthMeasurement)irl_rawPhysicalScreenHeight
+- (IRLRawMillimeters)irl_rawPhysicalScreenHeight
 {
-    return [self irl_rawPhysicalScreenSize].height;
+    return self.irl_rawPhysicalScreenSize.height;
 }
 
-- (IRLRawLengthMeasurement)irl_rawPhysicalScreenWidth
+- (IRLRawMillimeters)irl_rawPhysicalScreenWidth
 {
-    return [self irl_rawPhysicalScreenSize].width;
+    return self.irl_rawPhysicalScreenSize.width;
 }
 
 @end
diff --git a/Pod/Classes/iOS/UIView+IRLSize.h b/Pod/Classes/iOS/UIView+IRLSize.h
index 630c254..8deacb7 100644
--- a/Pod/Classes/iOS/UIView+IRLSize.h
+++ b/Pod/Classes/iOS/UIView+IRLSize.h
@@ -3,7 +3,7 @@
 //  IRLSize
 //
 //  Created by Jeff Kelley on 11/13/2014.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import <UIKit/UIKit.h>
@@ -14,39 +14,34 @@ NS_ASSUME_NONNULL_BEGIN
 
 @interface UIView (IRLSize)
 
-#if IRL_SUPPORTS_NSMEASUREMENT
 /**
  The physical height of the view on the screen, or @c nil if the view is displayed
  on a secondary screen. If the view is not on any screen, returns measurements for
  the main screen.
  */
-@property (nonatomic, readonly, nullable) NSMeasurement<NSUnitLength *> *irl_physicalHeight NS_SWIFT_NAME(physicalHeight) IRL_IOS_AVAILABLE(10.0);
-#endif
+@property (nonatomic, readonly, nullable) NSMeasurement<NSUnitLength *> *irl_physicalHeight NS_SWIFT_NAME(physicalHeight);
 
 /**
  The physical height of the view on the screen, or @c 0.0f if the view is displayed
  on a secondary screen. If the view is not on any screen, returns measurements for
  the main screen. Returned as a raw value in meters.
  */
-@property (nonatomic, readonly) IRLRawLengthMeasurement irl_rawPhysicalHeight NS_SWIFT_NAME(rawPhysicalHeight);
+@property (nonatomic, readonly) IRLRawMillimeters irl_rawPhysicalHeight NS_SWIFT_NAME(rawPhysicalHeight);
 
-#if IRL_SUPPORTS_NSMEASUREMENT
 /**
  The physical width of the view on the screen, or @c nil if the view is displayed
  on a secondary screen. If the view is not on any screen, returns measurements for
  the main screen.
  */
-@property (nonatomic, readonly, nullable) NSMeasurement<NSUnitLength *> *irl_physicalWidth NS_SWIFT_NAME(physicalWidth) IRL_IOS_AVAILABLE(10.0);
-#endif
+@property (nonatomic, readonly, nullable) NSMeasurement<NSUnitLength *> *irl_physicalWidth NS_SWIFT_NAME(physicalWidth);
 
 /**
  The physical width of the view on the screen, or @c 0.0f if the view is displayed
  on a secondary screen. If the view is not on any screen, returns measurements for
  the main screen. Returned as a raw value in meters.
  */
-@property (nonatomic, readonly) IRLRawLengthMeasurement irl_rawPhysicalWidth NS_SWIFT_NAME(rawPhysicalWidth);
+@property (nonatomic, readonly) IRLRawMillimeters irl_rawPhysicalWidth NS_SWIFT_NAME(rawPhysicalWidth);
 
-#if IRL_SUPPORTS_NSMEASUREMENT
 /**
  Calculates a transform that, when applied to the view, will make it a given height
  on the screen.
@@ -54,26 +49,24 @@ NS_ASSUME_NONNULL_BEGIN
  @param physicalHeight The desired physical height of the view on the screen.
 
  @return A @c CGAffineTransform that will achieve the desired height. If the view is
-         displayed on a secondary screen, the return value will be the view’s
-         current transform.
+ displayed on a secondary screen, the return value will be the view’s
+ current transform.
  */
-- (CGAffineTransform)irl_transformForPhysicalHeight:(NSMeasurement<NSUnitLength *> *)physicalHeight NS_SWIFT_NAME(transform(forPhysicalHeight:)) IRL_IOS_AVAILABLE(10.0);
-#endif
+- (CGAffineTransform)irl_transformForPhysicalHeight:(NSMeasurement<NSUnitLength *> *)physicalHeight NS_SWIFT_NAME(transform(forPhysicalHeight:));
 
 /**
  Calculates a transform that, when applied to the view, will make it a given height
  on the screen.
  
  @param rawPhysicalHeight The desired physical height of the view on the screen, as
-                          a raw value.
+ a raw value.
  
  @return A @c CGAffineTransform that will achieve the desired height. If the view is
  displayed on a secondary screen, the return value will be the view’s
  current transform.
  */
-- (CGAffineTransform)irl_transformForRawPhysicalHeight:(IRLRawLengthMeasurement)rawPhysicalHeight NS_SWIFT_NAME(transform(forRawPhysicalHeight:));
+- (CGAffineTransform)irl_transformForRawPhysicalHeight:(IRLRawMillimeters)rawPhysicalHeight NS_SWIFT_NAME(transform(forRawPhysicalHeight:));
 
-#if IRL_SUPPORTS_NSMEASUREMENT
 /**
  Calculates a transform that, when applied to the view, will make it a given width
  on the screen.
@@ -81,24 +74,23 @@ NS_ASSUME_NONNULL_BEGIN
  @param physicalWidth The desired physical width of the view on the screen.
  
  @return A @c CGAffineTransform that will achieve the desired width. If the view is
-         displayed on a secondary screen, the return value will be the view’s
-         current transform.
+ displayed on a secondary screen, the return value will be the view’s
+ current transform.
  */
-- (CGAffineTransform)irl_transformForPhysicalWidth:(NSMeasurement<NSUnitLength *> *)physicalWidth NS_SWIFT_NAME(transform(forPhysicalWidth:)) IRL_IOS_AVAILABLE(10.0);
-#endif
+- (CGAffineTransform)irl_transformForPhysicalWidth:(NSMeasurement<NSUnitLength *> *)physicalWidth NS_SWIFT_NAME(transform(forPhysicalWidth:));
 
 /**
  Calculates a transform that, when applied to the view, will make it a given width
  on the screen.
  
  @param rawPhysicalWidth The desired physical width of the view on the screen, as a
-                         raw value.
+ raw value.
  
  @return A @c CGAffineTransform that will achieve the desired width. If the view is
  displayed on a secondary screen, the return value will be the view’s
  current transform.
  */
-- (CGAffineTransform)irl_transformForRawPhysicalWidth:(IRLRawLengthMeasurement)rawPhysicalWidth NS_SWIFT_NAME(transform(forRawPhysicalWidth:));
+- (CGAffineTransform)irl_transformForRawPhysicalWidth:(IRLRawMillimeters)rawPhysicalWidth NS_SWIFT_NAME(transform(forRawPhysicalWidth:));
 
 @end
 
diff --git a/Pod/Classes/iOS/UIView+IRLSize.m b/Pod/Classes/iOS/UIView+IRLSize.m
index 03f0c26..78fe681 100644
--- a/Pod/Classes/iOS/UIView+IRLSize.m
+++ b/Pod/Classes/iOS/UIView+IRLSize.m
@@ -3,7 +3,7 @@
 //  IRLSize
 //
 //  Created by Jeff Kelley on 11/13/2014.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import "IRLSize.h"
@@ -12,7 +12,7 @@
 
 @implementation UIView (IRLSizePrivate)
 
-- (IRLRawSize)irl_rawPhysicalSize
+- (IRLRawDimensions)irl_rawPhysicalSize
 {
     return [UIDevice.currentDevice irl_rawPhysicalSizeOfView:self];
 }
@@ -31,7 +31,6 @@ - (BOOL)irl_isOnSecondaryScreen
 
 @implementation UIView (IRLSize)
 
-#if IRL_SUPPORTS_NSMEASUREMENT
 - (NSMeasurement<NSUnitLength *> *)irl_physicalWidth
 {
     if ([self irl_isOnSecondaryScreen]) {
@@ -39,7 +38,7 @@ @implementation UIView (IRLSize)
     }
     
     return [[NSMeasurement alloc] initWithDoubleValue:[self irl_rawPhysicalSize].width
-                                                 unit:IRL_RAW_SIZE_UNIT];
+                                                 unit:IRL_SIZE_UNIT];
 }
 
 - (NSMeasurement<NSUnitLength *> *)irl_physicalHeight
@@ -49,21 +48,19 @@ @implementation UIView (IRLSize)
     }
     
     return [[NSMeasurement alloc] initWithDoubleValue:[self irl_rawPhysicalSize].height
-                                                 unit:IRL_RAW_SIZE_UNIT];
+                                                 unit:IRL_SIZE_UNIT];
 }
-#endif
 
-- (IRLRawLengthMeasurement)irl_rawPhysicalWidth
+- (IRLRawMillimeters)irl_rawPhysicalWidth
 {
     return [self irl_rawPhysicalSize].width;
 }
 
-- (IRLRawLengthMeasurement)irl_rawPhysicalHeight
+- (IRLRawMillimeters)irl_rawPhysicalHeight
 {
     return [self irl_rawPhysicalSize].height;
 }
 
-#if IRL_SUPPORTS_NSMEASUREMENT
 - (CGAffineTransform)irl_transformForPhysicalWidth:(NSMeasurement<NSUnitLength *> *)physicalWidth
 {
     NSMeasurement<NSUnitLength *> *currentPhysicalWidth = self.irl_physicalWidth;
@@ -89,7 +86,7 @@ - (CGAffineTransform)irl_transformForPhysicalHeight:(NSMeasurement<NSUnitLength
 }
 
 - (CGAffineTransform)irl_scaleTransformForTargetMeasurement:(NSMeasurement *)target
-                                         currentMeasurement:(NSMeasurement *)current IRL_IOS_AVAILABLE(10.0)
+                                         currentMeasurement:(NSMeasurement *)current
 {
     if ([target canBeConvertedToUnit:current.unit]) {
         NSMeasurement *convertedTarget =
@@ -102,34 +99,33 @@ - (CGAffineTransform)irl_scaleTransformForTargetMeasurement:(NSMeasurement *)tar
         return self.transform;
     }
 }
-#endif
 
-- (CGAffineTransform)irl_transformForRawPhysicalWidth:(IRLRawLengthMeasurement)rawPhysicalWidth
+- (CGAffineTransform)irl_transformForRawPhysicalWidth:(IRLRawMillimeters)rawPhysicalWidth
 {
     if ([self irl_isOnSecondaryScreen]) {
         return self.transform;
     }
     
-    IRLRawLengthMeasurement currentValue = self.irl_rawPhysicalWidth;
+    IRLRawMillimeters currentValue = self.irl_rawPhysicalWidth;
     
     return [self irl_scaleTransformForTargetRawMeasurement:rawPhysicalWidth
                                      currentRawMeasurement:currentValue];
 }
 
-- (CGAffineTransform)irl_transformForRawPhysicalHeight:(IRLRawLengthMeasurement)rawPhysicalHeight
+- (CGAffineTransform)irl_transformForRawPhysicalHeight:(IRLRawMillimeters)rawPhysicalHeight
 {
     if ([self irl_isOnSecondaryScreen]) {
         return self.transform;
     }
     
-    IRLRawLengthMeasurement currentValue = self.irl_rawPhysicalHeight;
+    IRLRawMillimeters currentValue = self.irl_rawPhysicalHeight;
     
     return [self irl_scaleTransformForTargetRawMeasurement:rawPhysicalHeight
                                      currentRawMeasurement:currentValue];
 }
 
-- (CGAffineTransform)irl_scaleTransformForTargetRawMeasurement:(IRLRawLengthMeasurement)target
-                                         currentRawMeasurement:(IRLRawLengthMeasurement)current
+- (CGAffineTransform)irl_scaleTransformForTargetRawMeasurement:(IRLRawMillimeters)target
+                                         currentRawMeasurement:(IRLRawMillimeters)current
 {
     double ratio = target / current;
     
diff --git a/Pod/Classes/iOS/iOSDeviceConstants.h b/Pod/Classes/iOS/iOSDeviceConstants.h
new file mode 100644
index 0000000..84c13cb
--- /dev/null
+++ b/Pod/Classes/iOS/iOSDeviceConstants.h
@@ -0,0 +1,245 @@
+//
+//  iOSDeviceConstants.h
+//  IRLSize
+//
+//  Created by Jeff Kelley on 11/2/2018.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
+//
+
+#ifndef iOSDeviceConstants_h
+#define iOSDeviceConstants_h
+
+#pragma mark - Physical Measurements
+// All measurements are in millimeters, sourced from official, publicly-
+// available Apple device documentation here:
+//
+// https://developer.apple.com/accessories/
+
+/////////////
+// iPhones //
+/////////////
+
+// iPhone 5
+static const IRLRawMillimeters kiPhone5ScreenHeight = 90.39;
+static const IRLRawMillimeters kiPhone5ScreenWidth  = 51.70;
+
+// iPhone 5c
+static const IRLRawMillimeters kiPhone5cScreenHeight = 90.39;
+static const IRLRawMillimeters kiPhone5cScreenWidth  = 51.70;
+
+// iPhone 5s
+static const IRLRawMillimeters kiPhone5sScreenHeight = 90.39;
+static const IRLRawMillimeters kiPhone5sScreenWidth  = 51.70;
+
+// iPhone SE
+static const IRLRawMillimeters kiPhoneSEScreenHeight = 90.39;
+static const IRLRawMillimeters kiPhoneSEScreenWidth  = 51.70;
+
+// iPhone 6
+static const IRLRawMillimeters kiPhone6ScreenHeight = 104.05;
+static const IRLRawMillimeters kiPhone6ScreenWidth  =  58.50;
+
+// iPhone 6 Plus
+static const IRLRawMillimeters kiPhone6PlusScreenHeight = 121.54;
+static const IRLRawMillimeters kiPhone6PlusScreenWidth  =  68.36;
+
+// iPhone 6s
+static const IRLRawMillimeters kiPhone6sScreenHeight = 104.05;
+static const IRLRawMillimeters kiPhone6sScreenWidth  =  58.49;
+
+// iPhone 6s Plus
+static const IRLRawMillimeters kiPhone6sPlusScreenHeight = 121.54;
+static const IRLRawMillimeters kiPhone6sPlusScreenWidth  =  68.36;
+
+// iPhone 7
+static const IRLRawMillimeters kiPhone7ScreenHeight = 104.05;
+static const IRLRawMillimeters kiPhone7ScreenWidth  =  58.50;
+
+// iPhone 7 Plus
+static const IRLRawMillimeters kiPhone7PlusScreenHeight = 121.54;
+static const IRLRawMillimeters kiPhone7PlusScreenWidth  =  68.36;
+
+// iPhone 8
+static const IRLRawMillimeters kiPhone8ScreenHeight = 104.05;
+static const IRLRawMillimeters kiPhone8ScreenWidth  =  58.50;
+
+// iPhone 8 Plus
+static const IRLRawMillimeters kiPhone8PlusScreenHeight = 121.54;
+static const IRLRawMillimeters kiPhone8PlusScreenWidth  =  68.36;
+
+// iPhone X
+static const IRLRawMillimeters kiPhoneXScreenHeight = 135.75;
+static const IRLRawMillimeters kiPhoneXScreenWidth  =  63.12;
+
+// iPhone XR
+static const IRLRawMillimeters kiPhoneXRScreenHeight = 139.78;
+static const IRLRawMillimeters kiPhoneXRScreenWidth  =  64.58;
+
+// iPhone XS
+static const IRLRawMillimeters kiPhoneXSScreenHeight = 135.75;
+static const IRLRawMillimeters kiPhoneXSScreenWidth  =  63.13;
+
+// iPhone XS Max
+static const IRLRawMillimeters kiPhoneXSMaxScreenHeight = 149.71;
+static const IRLRawMillimeters kiPhoneXSMaxScreenWidth  =  69.61;
+
+
+///////////
+// iPads //
+///////////
+
+// iPad 4
+static const IRLRawMillimeters kiPad4ScreenHeight = 198.1;
+static const IRLRawMillimeters kiPad4ScreenWidth  = 149.0;
+
+// iPad mini
+static const IRLRawMillimeters kiPadMiniScreenHeight = 161.2;
+static const IRLRawMillimeters kiPadMiniScreenWidth  = 121.3;
+
+// iPad Air
+static const IRLRawMillimeters kiPadAirScreenHeight = 198.1;
+static const IRLRawMillimeters kiPadAirScreenWidth  = 149.0;
+
+// iPad mini 2
+static const IRLRawMillimeters kiPadMini2ScreenHeight = 161.2;
+static const IRLRawMillimeters kiPadMini2ScreenWidth  = 121.3;
+
+// iPad mini 3
+static const IRLRawMillimeters kiPadMini3ScreenHeight = 161.2;
+static const IRLRawMillimeters kiPadMini3ScreenWidth  = 121.3;
+
+// iPad Air 2
+static const IRLRawMillimeters kiPadAir2ScreenHeight = 203.11;
+static const IRLRawMillimeters kiPadAir2ScreenWidth  = 153.71;
+
+// iPad mini 4
+static const IRLRawMillimeters kiPadMini4ScreenHeight = 161.24;
+static const IRLRawMillimeters kiPadMini4ScreenWidth  = 121.31;
+
+// iPad Pro (12.9 Inch, 1st Generation)
+static const IRLRawMillimeters kiPadPro12_9InchScreenHeight = 262.27; // Not in diagram, sourced from second-gen (width measurement is the same)
+static const IRLRawMillimeters kiPadPro12_9InchScreenWidth  = 196.61;
+
+// iPad Pro (9.7 Inch)
+static const IRLRawMillimeters kiPadPro9_7InchScreenHeight = 203.11;
+static const IRLRawMillimeters kiPadPro9_7InchScreenWidth  = 153.71;
+
+// iPad 5
+static const IRLRawMillimeters kiPad5ScreenHeight = 196.47;
+static const IRLRawMillimeters kiPad5ScreenWidth  = 147.97;
+
+// iPad 6
+static const IRLRawMillimeters kiPad6ScreenHeight = 196.47;
+static const IRLRawMillimeters kiPad6ScreenWidth  = 147.97;
+
+// iPad Pro (12.9 Inch, 2nd Generation)
+static const IRLRawMillimeters kiPadPro12_9Inch2ScreenHeight = 262.27;
+static const IRLRawMillimeters kiPadPro12_9Inch2ScreenWidth  = 196.61;
+
+// iPad Pro (10.5 Inch)
+static const IRLRawMillimeters kiPadPro10_5InchScreenHeight = 213.50;
+static const IRLRawMillimeters kiPadPro10_5InchScreenWidth  = 160.13;
+
+/////////////////
+// iPods touch //
+/////////////////
+
+// iPod touch 5
+static const IRLRawMillimeters kiPodTouch5ScreenHeight = 88.61;
+static const IRLRawMillimeters kiPodTouch5ScreenWidth  = 49.92;
+
+// iPod touch 6
+static const IRLRawMillimeters kiPodTouch6ScreenHeight = 88.61;
+static const IRLRawMillimeters kiPodTouch6ScreenWidth  = 49.92;
+
+#pragma mark - Estimated Measurements
+// Estimated heights for unknown devices use the most-recently-known height for
+// that screen size. These are used in the case of an unknown model identifier
+// (usually a new device) that shares a screen resolution with a known device.
+
+///////////////////////
+// iPhone/iPod touch //
+///////////////////////
+
+// 3.5"
+// None of the devices in the specifications I could find were 3.5" devices, so
+// these are the estimates from the previous version (1.3.0) of IRLSize.
+static const IRLRawMillimeters kiPhone3_5InchScreenHeight = 74.0;
+static const IRLRawMillimeters kiPhone3_5InchScreenWidth = 49.3f;
+
+// 4.0"
+static const IRLRawMillimeters kiPhone4_0InchScreenHeight = kiPhoneSEScreenHeight;
+static const IRLRawMillimeters kiPhone4_0InchScreenWidth = kiPhoneSEScreenWidth;
+
+// 4.7"
+static const IRLRawMillimeters kiPhone4_7InchScreenHeight = kiPhone8ScreenHeight;
+static const IRLRawMillimeters kiPhone4_7InchScreenWidth = kiPhone8ScreenWidth;
+
+// 5.5"
+static const IRLRawMillimeters kiPhone5_5InchScreenHeight = kiPhone8PlusScreenHeight;
+static const IRLRawMillimeters kiPhone5_5InchScreenWidth = kiPhone8PlusScreenWidth;
+
+// 5.8"
+static const IRLRawMillimeters kiPhone5_8InchScreenHeight = kiPhoneXSScreenHeight;
+static const IRLRawMillimeters kiPhone5_8InchScreenWidth = kiPhoneXSScreenWidth;
+
+// 6.1"
+static const IRLRawMillimeters kiPhone6_1InchScreenHeight = kiPhoneXRScreenHeight;
+static const IRLRawMillimeters kiPhone6_1InchScreenWidth = kiPhoneXRScreenWidth;
+
+// 6.5"
+static const IRLRawMillimeters kiPhone6_5InchScreenHeight = kiPhoneXSMaxScreenHeight;
+static const IRLRawMillimeters kiPhone6_5InchScreenWidth = kiPhoneXSMaxScreenWidth;
+
+//////////
+// iPad //
+//////////
+
+// 7.9"
+// Since both iPad mini and iPad have the same resolution, we can't use the
+// 7.9" screen dimensions for estimating. Keeping this here but marked as
+// __unused in case future iPad mini models have some other method of
+// disambiguating what they are if model identifier and resolution don't work
+// (e.g. if the next iPad mini has the same screen size but is 3x instead of
+// 2x).
+__unused static const IRLRawMillimeters kiPad7_9InchScreenHeight = kiPadMini4ScreenHeight;
+__unused static const IRLRawMillimeters kiPad7_9InchScreenWidth = kiPadMini4ScreenWidth;
+
+// 9.7"
+static const IRLRawMillimeters kiPad9_7InchScreenHeight = kiPad6ScreenHeight;
+static const IRLRawMillimeters kiPad9_7InchScreenWidth = kiPad6ScreenWidth;
+
+// 10.5"
+static const IRLRawMillimeters kiPad10_5InchScreenHeight = kiPadPro10_5InchScreenHeight;
+static const IRLRawMillimeters kiPad10_5InchScreenWidth = kiPadPro10_5InchScreenWidth;
+
+// 12.9"
+static const IRLRawMillimeters kiPad12_9InchScreenHeight = kiPadPro12_9Inch2ScreenHeight;
+static const IRLRawMillimeters kiPad12_9InchScreenWidth = kiPadPro12_9Inch2ScreenWidth;
+
+#pragma mark - Screen Heights
+// When we estimate the size of the device, we use its height in points. This is
+// due to the fact that some iPhone sizes differ *only* in height. If, in the
+// future, a device is released that shares a height and not width with other
+// devices, we’ll have to use both width and height.
+
+///////////////////////
+// iPhone/iPod touch //
+///////////////////////
+static const NSUInteger kiPhone3_5InchHeightPoints = 480;
+static const NSUInteger kiPhone4_0InchHeightPoints = 568;
+static const NSUInteger kiPhone4_7InchHeightPoints = 667;
+static const NSUInteger kiPhone5_5InchHeightPoints = 736;
+static const NSUInteger kiPhone5_8InchHeightPoints = 812;
+// The 6.1" and 6.5" phones both have 896 height points, so we'll need to use
+// different techniques to identify them.
+static const NSUInteger kiPhone6_1InchHeightPoints = 896;
+
+//////////
+// iPad //
+//////////
+static const NSUInteger kiPad9_7InchHeightPoints = 1024;
+static const NSUInteger kiPadPro10_5InchHeightPoints = 1112;
+static const NSUInteger kiPadPro12_9InchHeightPoints = 1366;
+
+#endif /* iOSDeviceConstants_h */
diff --git a/Pod/Classes/watchOS/WKInterfaceDevice+IRLSize.h b/Pod/Classes/watchOS/WKInterfaceDevice+IRLSize.h
index 1d6bfc0..49066a9 100644
--- a/Pod/Classes/watchOS/WKInterfaceDevice+IRLSize.h
+++ b/Pod/Classes/watchOS/WKInterfaceDevice+IRLSize.h
@@ -3,7 +3,7 @@
 //  IRLSize
 //
 //  Created by Jeff Kelley on 6/29/2016.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import <WatchKit/WatchKit.h>
@@ -12,29 +12,25 @@ NS_ASSUME_NONNULL_BEGIN
 
 @interface WKInterfaceDevice (IRLSize)
 
-#if IRL_SUPPORTS_NSMEASUREMENT
 /**
  The physical height of the device’s screen.
  */
-@property (nonatomic, readonly) NSMeasurement<NSUnitLength *> *irl_physicalScreenHeight NS_SWIFT_NAME(physicalScreenHeight) IRL_WATCHOS_AVAILABLE(3.0);
-#endif
+@property (nonatomic, readonly) NSMeasurement<NSUnitLength *> *irl_physicalScreenHeight NS_SWIFT_NAME(physicalScreenHeight);
 
 /**
  The physical height of the device’s screen as a raw value.
  */
-@property (nonatomic, readonly) IRLRawLengthMeasurement irl_rawPhysicalScreenHeight NS_SWIFT_NAME(rawPhysicalScreenHeight);
+@property (nonatomic, readonly) IRLRawMillimeters irl_rawPhysicalScreenHeight NS_SWIFT_NAME(rawPhysicalScreenHeight);
 
-#if IRL_SUPPORTS_NSMEASUREMENT
 /**
  The physical width of the device’s screen.
  */
-@property (nonatomic, readonly) NSMeasurement<NSUnitLength *> *irl_physicalScreenWidth NS_SWIFT_NAME(physicalScreenWidth) IRL_WATCHOS_AVAILABLE(3.0);
-#endif
+@property (nonatomic, readonly) NSMeasurement<NSUnitLength *> *irl_physicalScreenWidth NS_SWIFT_NAME(physicalScreenWidth);
 
 /**
  The physical width of the device’s screen as a raw value.
  */
-@property (nonatomic, readonly) IRLRawLengthMeasurement irl_rawPhysicalScreenWidth NS_SWIFT_NAME(rawPhysicalScreenWidth);
+@property (nonatomic, readonly) IRLRawMillimeters irl_rawPhysicalScreenWidth NS_SWIFT_NAME(rawPhysicalScreenWidth);
 
 @end
 
diff --git a/Pod/Classes/watchOS/WKInterfaceDevice+IRLSize.m b/Pod/Classes/watchOS/WKInterfaceDevice+IRLSize.m
index 89f7ebc..f46cf76 100644
--- a/Pod/Classes/watchOS/WKInterfaceDevice+IRLSize.m
+++ b/Pod/Classes/watchOS/WKInterfaceDevice+IRLSize.m
@@ -3,23 +3,22 @@
 //  IRLSize
 //
 //  Created by Jeff Kelley on 6/29/2016.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import "IRLSize.h"
 
 #import <SDVersion/SDVersion.h>
 
-
 // https://www.sven.de/dpi/ is a good resource for determining screen sizes.
-static const float kAppleWatch38mmScreenWidth = 0.0212f;
-static const float kAppleWatch38mmScreenHeight = 0.0265f;
-static const float kAppleWatch40mmScreenWidth = 0.029f;
-static const float kAppleWatch40mmScreenHeight = 0.0353f;
-static const float kAppleWatch42mmScreenWidth = 0.0243f;
-static const float kAppleWatch42mmScreenHeight = 0.0304f;
-static const float kAppleWatch44mmScreenWidth = 0.0322f;
-static const float kAppleWatch44mmScreenHeight = 0.0393f;
+static const IRLRawMillimeters kAppleWatch38mmScreenWidth = 21.2;
+static const IRLRawMillimeters kAppleWatch38mmScreenHeight = 26.5;
+static const IRLRawMillimeters kAppleWatch40mmScreenWidth = 29.0;
+static const IRLRawMillimeters kAppleWatch40mmScreenHeight = 35.3;
+static const IRLRawMillimeters kAppleWatch42mmScreenWidth = 24.3;
+static const IRLRawMillimeters kAppleWatch42mmScreenHeight = 30.4;
+static const IRLRawMillimeters kAppleWatch44mmScreenWidth = 32.2;
+static const IRLRawMillimeters kAppleWatch44mmScreenHeight = 39.3;
 
 static const NSUInteger kAppleWatch38mmHeightPoints = 170;
 static const NSUInteger kAppleWatch40mmHeightPoints = 197;
@@ -28,9 +27,9 @@
 
 @implementation WKInterfaceDevice (IRLSize)
 
-- (IRLRawSize)irl_estimatedRawPhysicalScreenSizeFromScreenPointHeight
+- (IRLRawDimensions)irl_estimatedRawPhysicalScreenSizeFromScreenPointHeight
 {
-    IRLRawSize estimatedDimensions = { 0.0f, 0.0f };
+    IRLRawDimensions estimatedDimensions = { 0.0f, 0.0f };
     
     NSUInteger heightPoints = round(CGRectGetHeight(self.screenBounds));
     
@@ -59,9 +58,9 @@ - (IRLRawSize)irl_estimatedRawPhysicalScreenSizeFromScreenPointHeight
     return estimatedDimensions;
 }
 
-- (IRLRawSize)irl_rawPhysicalScreenSize
+- (IRLRawDimensions)irl_rawPhysicalScreenSize
 {
-    IRLRawSize size = { 0.0f, 0.0f };
+    IRLRawDimensions size = { 0.0f, 0.0f };
     
     switch ([SDwatchOSVersion deviceVersion]) {
         case AppleWatch38mm:
@@ -83,30 +82,28 @@ - (IRLRawSize)irl_rawPhysicalScreenSize
     return size;
 }
 
-#if IRL_SUPPORTS_NSMEASUREMENT
 - (NSMeasurement<NSUnitLength *> *)irl_physicalScreenHeight
 {
-    IRLRawSize deviceDimensions = [self irl_rawPhysicalScreenSize];
+    IRLRawDimensions deviceDimensions = [self irl_rawPhysicalScreenSize];
     
     return [[NSMeasurement alloc] initWithDoubleValue:deviceDimensions.height
-                                                 unit:IRL_RAW_SIZE_UNIT];
+                                                 unit:IRL_SIZE_UNIT];
 }
 
 - (NSMeasurement<NSUnitLength *> *)irl_physicalScreenWidth
 {
-    IRLRawSize deviceDimensions = [self irl_rawPhysicalScreenSize];
+    IRLRawDimensions deviceDimensions = [self irl_rawPhysicalScreenSize];
     
     return [[NSMeasurement alloc] initWithDoubleValue:deviceDimensions.width
-                                                 unit:IRL_RAW_SIZE_UNIT];
+                                                 unit:IRL_SIZE_UNIT];
 }
-#endif
 
-- (IRLRawLengthMeasurement)irl_rawPhysicalScreenHeight
+- (IRLRawMillimeters)irl_rawPhysicalScreenHeight
 {
     return [self irl_rawPhysicalScreenSize].height;
 }
 
-- (IRLRawLengthMeasurement)irl_rawPhysicalScreenWidth
+- (IRLRawMillimeters)irl_rawPhysicalScreenWidth
 {
     return [self irl_rawPhysicalScreenSize].width;
 }
diff --git a/Pod/Classes/watchOS/WKInterfaceObject+IRLSize.h b/Pod/Classes/watchOS/WKInterfaceObject+IRLSize.h
index cff567e..026deea 100644
--- a/Pod/Classes/watchOS/WKInterfaceObject+IRLSize.h
+++ b/Pod/Classes/watchOS/WKInterfaceObject+IRLSize.h
@@ -3,7 +3,7 @@
 //  IRLSize
 //
 //  Created by Jeff Kelley on 6/29/2016.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import <WatchKit/WatchKit.h>
@@ -14,37 +14,33 @@ NS_ASSUME_NONNULL_BEGIN
 
 @interface WKInterfaceObject (IRLSize)
 
-#if IRL_SUPPORTS_NSMEASUREMENT
 /**
  Sets the physical width of the interface object on screen.
 
  @param width The physical width to set on the interface object.
  */
-- (void)irl_setPhysicalWidth:(NSMeasurement<NSUnitLength *> *)width NS_SWIFT_NAME(setPhysicalWidth(_:)) IRL_WATCHOS_AVAILABLE(3.0);
-#endif
+- (void)irl_setPhysicalWidth:(NSMeasurement<NSUnitLength *> *)width NS_SWIFT_NAME(setPhysicalWidth(_:));
 
 /**
  Sets the physical width of the interface object on screen.
  
  @param width The physical width to set on the interface object as a raw value.
  */
-- (void)irl_setRawPhysicalWidth:(IRLRawLengthMeasurement)width NS_SWIFT_NAME(setRawPhysicalWidth(_:));
+- (void)irl_setRawPhysicalWidth:(IRLRawMillimeters)width NS_SWIFT_NAME(setRawPhysicalWidth(_:));
 
-#if IRL_SUPPORTS_NSMEASUREMENT
 /**
  Sets the physical height of the interface object on screen.
  
  @param height The physical height to set on the interface object.
  */
-- (void)irl_setPhysicalHeight:(NSMeasurement<NSUnitLength *> *)height NS_SWIFT_NAME(setPhysicalHeight(_:)) IRL_WATCHOS_AVAILABLE(3.0);
-#endif
+- (void)irl_setPhysicalHeight:(NSMeasurement<NSUnitLength *> *)height NS_SWIFT_NAME(setPhysicalHeight(_:));
 
 /**
  Sets the physical height of the interface object on screen.
  
  @param height The physical height to set on the interface object as a raw value.
  */
-- (void)irl_setRawPhysicalHeight:(IRLRawLengthMeasurement)height NS_SWIFT_NAME(setRawPhysicalHeight(_:));
+- (void)irl_setRawPhysicalHeight:(IRLRawMillimeters)height NS_SWIFT_NAME(setRawPhysicalHeight(_:));
 
 @end
 
diff --git a/Pod/Classes/watchOS/WKInterfaceObject+IRLSize.m b/Pod/Classes/watchOS/WKInterfaceObject+IRLSize.m
index e7481a5..acef831 100644
--- a/Pod/Classes/watchOS/WKInterfaceObject+IRLSize.m
+++ b/Pod/Classes/watchOS/WKInterfaceObject+IRLSize.m
@@ -3,14 +3,13 @@
 //  IRLSize
 //
 //  Created by Jeff Kelley on 6/29/2016.
-//  Copyright © 2017 Detroit Labs. All rights reserved.
+//  Copyright © 2018 Detroit Labs. All rights reserved.
 //
 
 #import "WKInterfaceObject+IRLSize.h"
 
 @implementation WKInterfaceObject (IRLSize)
 
-#if IRL_SUPPORTS_NSMEASUREMENT
 - (void)irl_setPhysicalWidth:(NSMeasurement<NSUnitLength *> *)width
 {
     NSMeasurement<NSUnitLength *> *screenWidth =
@@ -42,11 +41,10 @@ - (void)irl_setPhysicalHeight:(NSMeasurement<NSUnitLength *> *)height
         [self irl_setHeightRatio:ratio];
     }
 }
-#endif
 
-- (void)irl_setRawPhysicalWidth:(IRLRawLengthMeasurement)width
+- (void)irl_setRawPhysicalWidth:(IRLRawMillimeters)width
 {
-    IRLRawLengthMeasurement screenWidth =
+    IRLRawMillimeters screenWidth =
     [WKInterfaceDevice currentDevice].irl_rawPhysicalScreenWidth;
     
     double ratio = width / screenWidth;
@@ -54,9 +52,9 @@ - (void)irl_setRawPhysicalWidth:(IRLRawLengthMeasurement)width
     [self irl_setWidthRatio:ratio];
 }
 
-- (void)irl_setRawPhysicalHeight:(IRLRawLengthMeasurement)height
+- (void)irl_setRawPhysicalHeight:(IRLRawMillimeters)height
 {
-    IRLRawLengthMeasurement screenHeight =
+    IRLRawMillimeters screenHeight =
     [WKInterfaceDevice currentDevice].irl_rawPhysicalScreenHeight;
     
     double ratio = height / screenHeight;
diff --git a/README.md b/README.md
index a18a514..30331a5 100644
--- a/README.md
+++ b/README.md
@@ -17,7 +17,11 @@ pod install --project-directory=Example
 
 ## Use
 
-All IRLSize methods have two versions: one that uses `NSMeasurement` in iOS 10/watchOS 3 and later, and one that uses the `IRLRawLengthMeasurement` type (a float measuring meters).
+All IRLSize methods have two versions: one that uses `NSMeasurement` (`Measurement` in Swift), and one that uses the `IRLRawMillimeters` type (a `double` measuring millimeters).
+
+### Important: Upgrading to IRLSize 2.0
+
+IRLSize 2.0 switched the native unit for measurements from meters to millimeters to better manage what official Apple documentation there is on device sizes. This is a breaking change and as such the raw unit type changed from `IRLRawLengthMeasurement` to `IRLRawMillimeters` to avoid this change accidentally changing existing code by a factor of 1,000. If you were using `NSMeasurement`, no updates should be necessary, as it automatically converts between units.
 
 ### Measuring an On-Screen Element
 
@@ -31,10 +35,9 @@ NSMeasurement<NSUnitLength *> *width = view.irl_physicalWidth;
 NSMeasurement<NSUnitLength *> *height = view.irl_physicalHeight;
 
 // Raw Version
-//   IRLRawLengthMeasurement is a `float` representing meters for OSes versions that
-//   don’t support `NSMeasurement`. 
-IRLRawLengthMeasurement rawWidth = view.irl_rawPhysicalWidth;
-IRLRawLengthMeasurement rawHeight = view.irl_rawPhysicalHeight;
+//   `IRLRawMillimeters` is a `double` representing millimeters. 
+IRLRawMillimeters rawWidth = view.irl_rawPhysicalWidth;
+IRLRawMillimeters rawHeight = view.irl_rawPhysicalHeight;
 ```
 
 If a view is on a secondary screen (i.e. if you’re using an external display)
@@ -49,8 +52,8 @@ let width = view.physicalWidth // type: Measurement<UnitLength>
 let height = view.physicalHeight // type: Measurement<UnitLength>
 
 // Raw Version
-let rawWidth = view.rawPhysicalWidth // type: IRLRawLengthMeasurement
-let rawHeight = view.rawPhysicalHeight // type: IRLRawLengthMeasurement
+let rawWidth = view.rawPhysicalWidth // type: IRLRawMillimeters
+let rawHeight = view.rawPhysicalHeight // type: IRLRawMillimeters
 ```
 
 ### Sizing a View
@@ -68,7 +71,7 @@ NSMeasurement<NSUnitLength *> *desiredHeight =
 view.transform = [view irl_transformForPhysicalHeight:desiredHeight];
 
 // Raw Version
-view.transform = [view irl_transformForRawPhysicalHeight:0.038];
+view.transform = [view irl_transformForRawPhysicalHeight:38.0];
 ```
 
 #### Swift
@@ -79,7 +82,7 @@ let desiredHeight = Measurement(value: 38, unit: UnitLength.millimeters)
 view.transform = view.transform(forPhysicalHeight:desiredHeight)
 
 // Raw Version
-view.transform = view.transform(forRawPhysicalHeight:0.038);
+view.transform = view.transform(forRawPhysicalHeight:38);
 ```
 
 ### Measuring a Device
@@ -91,11 +94,11 @@ If you just want to know the physical size of the screen, use the category on
 ```Objective-C
 // iOS
 NSMeasurement<NSUnitLength *> *screenHeight = UIDevice.currentDevice.irl_physicalScreenHeight;
-IRLRawLengthMeasurement rawScreenHeight = UIDevice.currentDevice.irl_rawPhysicalScreenHeight;
+IRLRawMillimeters rawScreenHeight = UIDevice.currentDevice.irl_rawPhysicalScreenHeight;
 
 // watchOS
 NSMeasurement<NSUnitLength *> *screenHeight = WKInterfaceDevice.currentDevice.irl_physicalScreenHeight;
-IRLRawLengthMeasurement rawScreenHeight = WKInterfaceDevice.currentDevice.irl_rawPhysicalScreenHeight;
+IRLRawMillimeters rawScreenHeight = WKInterfaceDevice.currentDevice.irl_rawPhysicalScreenHeight;
 ```
 
 #### Swift
diff --git a/travis-build.sh b/travis-build.sh
index fe46cd9..45ff51d 100755
--- a/travis-build.sh
+++ b/travis-build.sh
@@ -4,7 +4,7 @@ set -ev
 
 rc=0
 
-for OS in 10.0 10.1 10.2 10.3; do 
+for OS in 10.3 11.4 12.0; do 
 	for device in "iPhone SE" "iPhone 7" "iPhone 7 Plus" "iPad Pro (9.7 inch)" "iPad Pro (12.9 inch)"; do
 		xcodebuild -workspace "Example/IRLSizeExample.xcworkspace" \
 		           -scheme "IRLSizeExample" \