diff --git a/.github/CODEOWNERS b/.github/CODEOWNERS
new file mode 100644
index 000000000..ccae20932
--- /dev/null
+++ b/.github/CODEOWNERS
@@ -0,0 +1 @@
+* @frankus @LuqKhan
diff --git a/Apptentive/Apptentive.xcodeproj/project.pbxproj b/Apptentive/Apptentive.xcodeproj/project.pbxproj
index 0df739005..44c5d1832 100644
--- a/Apptentive/Apptentive.xcodeproj/project.pbxproj
+++ b/Apptentive/Apptentive.xcodeproj/project.pbxproj
@@ -18,6 +18,8 @@
 		0116D5271E92F516001DA5CF /* ApptentiveMessageStore.h in Headers */ = {isa = PBXBuildFile; fileRef = 0116D5251E92F516001DA5CF /* ApptentiveMessageStore.h */; };
 		0116D5281E92F516001DA5CF /* ApptentiveMessageStore.m in Sources */ = {isa = PBXBuildFile; fileRef = 0116D5261E92F516001DA5CF /* ApptentiveMessageStore.m */; };
 		01201AD31FC637BE00EB3593 /* CodePointAndInteractionTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 01201AD21FC637BD00EB3593 /* CodePointAndInteractionTests.m */; };
+		01211CEB268146E7009F0364 /* ApptentiveRandom.h in Headers */ = {isa = PBXBuildFile; fileRef = 01211CE9268146E7009F0364 /* ApptentiveRandom.h */; };
+		01211CEC268146E7009F0364 /* ApptentiveRandom.m in Sources */ = {isa = PBXBuildFile; fileRef = 01211CEA268146E7009F0364 /* ApptentiveRandom.m */; };
 		01216C501EBBB53E0062BD0D /* RequestTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 01216C4F1EBBB53E0062BD0D /* RequestTests.swift */; };
 		0123005F20531698000EC3C3 /* ClauseTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 0123005E20531698000EC3C3 /* ClauseTests.m */; };
 		012B96C325118349008A56CC /* Apptentive.h in Headers */ = {isa = PBXBuildFile; fileRef = 012B96C22511832D008A56CC /* Apptentive.h */; settings = {ATTRIBUTES = (Public, ); }; };
@@ -371,6 +373,8 @@
 		01B9055C2411C83600E2A663 /* ApptentiveArchiver.m in Sources */ = {isa = PBXBuildFile; fileRef = 01B9055A2411C83600E2A663 /* ApptentiveArchiver.m */; };
 		01B9057E2416C52B00E2A663 /* ApptentiveURLOpener.h in Headers */ = {isa = PBXBuildFile; fileRef = 01B9057C2416C52B00E2A663 /* ApptentiveURLOpener.h */; };
 		01B9057F2416C52B00E2A663 /* ApptentiveURLOpener.m in Sources */ = {isa = PBXBuildFile; fileRef = 01B9057D2416C52B00E2A663 /* ApptentiveURLOpener.m */; };
+		01D43A2826B3688200963752 /* UIWindow+Apptentive.h in Headers */ = {isa = PBXBuildFile; fileRef = 01D43A2626B3688200963752 /* UIWindow+Apptentive.h */; };
+		01D43A2926B3688200963752 /* UIWindow+Apptentive.m in Sources */ = {isa = PBXBuildFile; fileRef = 01D43A2726B3688200963752 /* UIWindow+Apptentive.m */; };
 		01E04F9E1E819CD300D7E849 /* ApptentiveMessageManager.h in Headers */ = {isa = PBXBuildFile; fileRef = 01E04F9C1E819CD300D7E849 /* ApptentiveMessageManager.h */; };
 		01E04F9F1E819CD300D7E849 /* ApptentiveMessageManager.m in Sources */ = {isa = PBXBuildFile; fileRef = 01E04F9D1E819CD300D7E849 /* ApptentiveMessageManager.m */; };
 		01E8E2361E6E096D00786738 /* ApptentiveInteractionAppleRatingDialogController.h in Headers */ = {isa = PBXBuildFile; fileRef = 01E8E2341E6E096D00786738 /* ApptentiveInteractionAppleRatingDialogController.h */; };
@@ -461,6 +465,8 @@
 		0116D5251E92F516001DA5CF /* ApptentiveMessageStore.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ApptentiveMessageStore.h; sourceTree = "<group>"; };
 		0116D5261E92F516001DA5CF /* ApptentiveMessageStore.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ApptentiveMessageStore.m; sourceTree = "<group>"; };
 		01201AD21FC637BD00EB3593 /* CodePointAndInteractionTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = CodePointAndInteractionTests.m; sourceTree = "<group>"; };
+		01211CE9268146E7009F0364 /* ApptentiveRandom.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = ApptentiveRandom.h; sourceTree = "<group>"; };
+		01211CEA268146E7009F0364 /* ApptentiveRandom.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = ApptentiveRandom.m; sourceTree = "<group>"; };
 		01216C4F1EBBB53E0062BD0D /* RequestTests.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = RequestTests.swift; sourceTree = "<group>"; };
 		0123005E20531698000EC3C3 /* ClauseTests.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = ClauseTests.m; sourceTree = "<group>"; };
 		012B96C22511832D008A56CC /* Apptentive.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = Apptentive.h; sourceTree = "<group>"; };
@@ -842,6 +848,8 @@
 		01B9057C2416C52B00E2A663 /* ApptentiveURLOpener.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = ApptentiveURLOpener.h; sourceTree = "<group>"; };
 		01B9057D2416C52B00E2A663 /* ApptentiveURLOpener.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = ApptentiveURLOpener.m; sourceTree = "<group>"; };
 		01BEA06D2511E97500DF982D /* Apptentive.modulemap */ = {isa = PBXFileReference; lastKnownFileType = "sourcecode.module-map"; path = Apptentive.modulemap; sourceTree = "<group>"; };
+		01D43A2626B3688200963752 /* UIWindow+Apptentive.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "UIWindow+Apptentive.h"; sourceTree = "<group>"; };
+		01D43A2726B3688200963752 /* UIWindow+Apptentive.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = "UIWindow+Apptentive.m"; sourceTree = "<group>"; };
 		01E04F9C1E819CD300D7E849 /* ApptentiveMessageManager.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ApptentiveMessageManager.h; sourceTree = "<group>"; };
 		01E04F9D1E819CD300D7E849 /* ApptentiveMessageManager.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ApptentiveMessageManager.m; sourceTree = "<group>"; };
 		01E8E2341E6E096D00786738 /* ApptentiveInteractionAppleRatingDialogController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ApptentiveInteractionAppleRatingDialogController.h; sourceTree = "<group>"; };
@@ -1195,6 +1203,8 @@
 				01AA89B61F18177E00FB59AB /* ApptentiveAppInstall.h */,
 				01AA89B71F18177E00FB59AB /* ApptentiveAppInstall.m */,
 				0178C5681FC4A57900DABF39 /* Targeting */,
+				01211CE9268146E7009F0364 /* ApptentiveRandom.h */,
+				01211CEA268146E7009F0364 /* ApptentiveRandom.m */,
 			);
 			path = Model;
 			sourceTree = "<group>";
@@ -1522,6 +1532,8 @@
 				01B9055A2411C83600E2A663 /* ApptentiveArchiver.m */,
 				01B9057C2416C52B00E2A663 /* ApptentiveURLOpener.h */,
 				01B9057D2416C52B00E2A663 /* ApptentiveURLOpener.m */,
+				01D43A2626B3688200963752 /* UIWindow+Apptentive.h */,
+				01D43A2726B3688200963752 /* UIWindow+Apptentive.m */,
 			);
 			path = Misc;
 			sourceTree = "<group>";
@@ -1784,6 +1796,7 @@
 				01A2D1031E490A9700C2103A /* ApptentivePassThroughWindow.h in Headers */,
 				01A2D1391E490A9700C2103A /* ApptentivePerson.h in Headers */,
 				01A2D13F1E490A9700C2103A /* ApptentiveState.h in Headers */,
+				01211CEB268146E7009F0364 /* ApptentiveRandom.h in Headers */,
 				EFC308D71ECA6692006B6D36 /* ApptentiveLegacyConversationRequest.h in Headers */,
 				EF4EAB91203F8A57003318C9 /* ApptentiveDispatchTask+Internal.h in Headers */,
 				01A2D1781E490A9700C2103A /* ApptentiveAboutViewController.h in Headers */,
@@ -1831,6 +1844,7 @@
 				012ED9292072F33F003D87F3 /* ApptentiveRetryPolicy.h in Headers */,
 				EF4EABAB2040C0CF003318C9 /* ApptentiveLogMonitorSession.h in Headers */,
 				EF9009901F8D370400DC5B56 /* ApptentiveLogMonitor.h in Headers */,
+				01D43A2826B3688200963752 /* UIWindow+Apptentive.h in Headers */,
 				EF8EE3AB1EBBA5D00033E7A1 /* ApptentiveJWT.h in Headers */,
 				01A2D1D81E490A9700C2103A /* ApptentiveDataManager.h in Headers */,
 				01A2D0FF1E490A9700C2103A /* ApptentiveNetworkImageIconView.h in Headers */,
@@ -1983,12 +1997,13 @@
 			isa = PBXProject;
 			attributes = {
 				LastSwiftUpdateCheck = 1200;
-				LastUpgradeCheck = 1200;
+				LastUpgradeCheck = 1250;
 				ORGANIZATIONNAME = "Apptentive, Inc.";
 				TargetAttributes = {
 					01A2CF901E49062700C2103A = {
 						CreatedOnToolsVersion = 8.2.1;
 						DevelopmentTeam = 86WML2UN43;
+						LastSwiftMigration = 1250;
 						ProvisioningStyle = Automatic;
 					};
 					01A2CF991E49062800C2103A = {
@@ -2284,6 +2299,7 @@
 				EFC308D31EC52915006B6D36 /* ApptentiveStopWatch.m in Sources */,
 				01A2D1261E490A9700C2103A /* ApptentiveDevice.m in Sources */,
 				010FE347203E4C810021C246 /* ApptentiveIndentPrinter.m in Sources */,
+				01D43A2926B3688200963752 /* UIWindow+Apptentive.m in Sources */,
 				01A2D1AB1E490A9700C2103A /* ApptentiveAppConfiguration.m in Sources */,
 				01A2D1D11E490A9700C2103A /* ApptentiveSerialRequest.m in Sources */,
 				0140D5FB1E833103007B5130 /* ApptentiveMessage.m in Sources */,
@@ -2294,6 +2310,7 @@
 				01A2D1E91E490A9700C2103A /* ApptentiveSurveyViewModel.m in Sources */,
 				014508A11EAAB26D003326E7 /* ApptentiveConversationRequest.m in Sources */,
 				018FAFE41FC4AC41007C52FE /* ApptentiveOrClause.m in Sources */,
+				01211CEC268146E7009F0364 /* ApptentiveRandom.m in Sources */,
 				01A2D1861E490A9700C2103A /* ApptentiveAttachmentCell.m in Sources */,
 				01A2D1FD1E490A9700C2103A /* ApptentiveSurveySingleLineCell.m in Sources */,
 				EF4EAB96203F8B99003318C9 /* ApptentiveLogFileWriteTask.m in Sources */,
@@ -2419,7 +2436,7 @@
 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
 				"CODE_SIGN_IDENTITY[sdk=iphoneos*]" = "iPhone Developer";
 				COPY_PHASE_STRIP = NO;
-				CURRENT_PROJECT_VERSION = 48;
+				CURRENT_PROJECT_VERSION = 49;
 				DEBUG_INFORMATION_FORMAT = dwarf;
 				ENABLE_STRICT_OBJC_MSGSEND = YES;
 				ENABLE_TESTABILITY = YES;
@@ -2477,7 +2494,7 @@
 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
 				"CODE_SIGN_IDENTITY[sdk=iphoneos*]" = "iPhone Developer";
 				COPY_PHASE_STRIP = NO;
-				CURRENT_PROJECT_VERSION = 48;
+				CURRENT_PROJECT_VERSION = 49;
 				DEBUG_INFORMATION_FORMAT = "dwarf-with-dsym";
 				ENABLE_NS_ASSERTIONS = NO;
 				ENABLE_STRICT_OBJC_MSGSEND = YES;
@@ -2505,11 +2522,12 @@
 		01A2CFA61E49062800C2103A /* Debug */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				CLANG_ENABLE_MODULES = YES;
 				CODE_SIGN_IDENTITY = "";
 				DEFINES_MODULE = YES;
 				DEVELOPMENT_TEAM = 86WML2UN43;
 				DYLIB_COMPATIBILITY_VERSION = 1;
-				DYLIB_CURRENT_VERSION = 48;
+				DYLIB_CURRENT_VERSION = 49;
 				DYLIB_INSTALL_NAME_BASE = "@rpath";
 				GCC_PREFIX_HEADER = "Apptentive/Misc/ApptentiveConnect-Prefix.pch";
 				GCC_PREPROCESSOR_DEFINITIONS = "APPTENTIVE_DEBUG=1";
@@ -2520,17 +2538,20 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.apptentive.Apptentive;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
+				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
+				SWIFT_VERSION = 5.0;
 			};
 			name = Debug;
 		};
 		01A2CFA71E49062800C2103A /* Release */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				CLANG_ENABLE_MODULES = YES;
 				CODE_SIGN_IDENTITY = "";
 				DEFINES_MODULE = YES;
 				DEVELOPMENT_TEAM = 86WML2UN43;
 				DYLIB_COMPATIBILITY_VERSION = 1;
-				DYLIB_CURRENT_VERSION = 48;
+				DYLIB_CURRENT_VERSION = 49;
 				DYLIB_INSTALL_NAME_BASE = "@rpath";
 				GCC_PREFIX_HEADER = "Apptentive/Misc/ApptentiveConnect-Prefix.pch";
 				INFOPLIST_FILE = Apptentive/Info.plist;
@@ -2540,6 +2561,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.apptentive.Apptentive;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
+				SWIFT_VERSION = 5.0;
 			};
 			name = Release;
 		};
diff --git a/Apptentive/Apptentive.xcodeproj/xcshareddata/xcschemes/Apptentive.xcscheme b/Apptentive/Apptentive.xcodeproj/xcshareddata/xcschemes/Apptentive.xcscheme
index f1e85f8c5..816b41894 100644
--- a/Apptentive/Apptentive.xcodeproj/xcshareddata/xcschemes/Apptentive.xcscheme
+++ b/Apptentive/Apptentive.xcodeproj/xcshareddata/xcschemes/Apptentive.xcscheme
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "1200"
+   LastUpgradeVersion = "1250"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
diff --git a/Apptentive/Apptentive.xcodeproj/xcshareddata/xcschemes/ApptentiveDebugging.xcscheme b/Apptentive/Apptentive.xcodeproj/xcshareddata/xcschemes/ApptentiveDebugging.xcscheme
index a9641d847..689dbc671 100644
--- a/Apptentive/Apptentive.xcodeproj/xcshareddata/xcschemes/ApptentiveDebugging.xcscheme
+++ b/Apptentive/Apptentive.xcodeproj/xcshareddata/xcschemes/ApptentiveDebugging.xcscheme
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "1200"
+   LastUpgradeVersion = "1250"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
diff --git a/Apptentive/Apptentive/Apptentive.m b/Apptentive/Apptentive/Apptentive.m
index 5c5f192e6..97b711077 100644
--- a/Apptentive/Apptentive/Apptentive.m
+++ b/Apptentive/Apptentive/Apptentive.m
@@ -26,6 +26,7 @@
 #import "ApptentiveVersion.h"
 #import "Apptentive_Private.h"
 #import "ApptentiveDispatchQueue.h"
+#import "UIWindow+Apptentive.h"
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -104,6 +105,7 @@ - (nullable instancetype)initWithApptentiveKey:(NSString *)apptentiveKey apptent
 		_shouldSanitizeLogMessages = YES;
 		_showInfoButton = YES;
 		_enableDebugLogFile = YES;
+		_gatherCarrierInfo = YES;
 	}
 	return self;
 }
@@ -157,7 +159,7 @@ - (id)initWithConfiguration:(ApptentiveConfiguration *)configuration {
 		
 		// start log writer
 		if (configuration.enableDebugLogFile) {
-			ApptentiveStartLogMonitor([ApptentiveUtilities cacheDirectoryPath:@"com.apptentive.logs"]);
+			ApptentiveStartLogWriter([ApptentiveUtilities cacheDirectoryPath:@"com.apptentive.logs"]);
 		}
 
 		// start log monitor
@@ -170,6 +172,8 @@ - (id)initWithConfiguration:(ApptentiveConfiguration *)configuration {
 		_appID = configuration.appID;
 
 		_showInfoButton = configuration.showInfoButton;
+
+		ApptentiveBackend.gatherCarrierInfo = configuration.gatherCarrierInfo;
 		
         _surveyTermsAndConditions = configuration.surveyTermsAndConditions;
         
@@ -1094,9 +1098,7 @@ @implementation ApptentiveNavigationController
 // Container to allow customization of Apptentive UI using UIAppearance
 
 - (void)presentAnimated:(BOOL)animated completion:(void (^__nullable)(void))completion {
-	self.apptentiveAlertWindow = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
-	self.apptentiveAlertWindow.rootViewController = [[UIViewController alloc] init];
-	self.apptentiveAlertWindow.windowLevel = UIWindowLevelAlert + 1;
+	self.apptentiveAlertWindow = [UIWindow apptentive_windowWithRootViewController:[[UIViewController alloc] init]];
 	[self.apptentiveAlertWindow makeKeyAndVisible];
 	[self.apptentiveAlertWindow.rootViewController presentViewController:self animated:animated completion:completion];
 }
diff --git a/Apptentive/Apptentive/ApptentiveMain.h b/Apptentive/Apptentive/ApptentiveMain.h
index 834492508..acb703d0a 100644
--- a/Apptentive/Apptentive/ApptentiveMain.h
+++ b/Apptentive/Apptentive/ApptentiveMain.h
@@ -20,7 +20,7 @@ FOUNDATION_EXPORT double ApptentiveVersionNumber;
 FOUNDATION_EXPORT const unsigned char ApptentiveVersionString[];
 
 /** The version number of the Apptentive SDK. */
-#define kApptentiveVersionString @"5.3.3"
+#define kApptentiveVersionString @"5.3.4"
 
 /** The version number of the Apptentive API platform. */
 #define kApptentiveAPIVersionString @"9"
@@ -186,6 +186,9 @@ typedef NS_ENUM(NSUInteger, ApptentiveLogLevel) {
 /** If set, shows a valid combination of terms & conditions and/or a link with an optional text mask, below the submit button in Surveys. */
 @property (copy, nonatomic, nullable) TermsAndConditions* surveyTermsAndConditions;
 
+/** If set, uses the CoreTelephony framework to expose the mobile carrier name to the targeting system. Defaults to `YES`. */
+@property (assign, nonatomic) BOOL gatherCarrierInfo;
+
 /**
  Returns an instance of the `ApptentiveConfiguration` class
  initialized with the specified parameters.
diff --git a/Apptentive/Apptentive/Custom Views/ApptentiveHUDViewController.m b/Apptentive/Apptentive/Custom Views/ApptentiveHUDViewController.m
index 8d8e838d4..9c9c098e1 100644
--- a/Apptentive/Apptentive/Custom Views/ApptentiveHUDViewController.m	
+++ b/Apptentive/Apptentive/Custom Views/ApptentiveHUDViewController.m	
@@ -8,6 +8,7 @@
 
 #import "ApptentiveHUDViewController.h"
 #import "ApptentivePassThroughWindow.h"
+#import "UIWindow+Apptentive.h"
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -94,11 +95,9 @@ - (void)showInAlertWindow {
 	self.interval = self.interval ?: 2.0;
 	self.animationDuration = fmin(self.animationDuration ?: 0.25, self.interval / 2.0);
 
-	self.hostWindow = [[ApptentivePassThroughWindow alloc] init];
-
+	
+	self.hostWindow = [ApptentivePassThroughWindow apptentive_windowWithRootViewController:self];
 	[self.hostWindow makeKeyAndVisible];
-	self.hostWindow.rootViewController = self;
-	self.hostWindow.windowLevel = UIWindowLevelAlert;
 	self.hostWindow.backgroundColor = [UIColor clearColor];
 
 	self.HUDView.alpha = 0.0;
diff --git a/Apptentive/Apptentive/Engagement/Model/ApptentiveConversation.h b/Apptentive/Apptentive/Engagement/Model/ApptentiveConversation.h
index b74e958b5..8a70064be 100644
--- a/Apptentive/Apptentive/Engagement/Model/ApptentiveConversation.h
+++ b/Apptentive/Apptentive/Engagement/Model/ApptentiveConversation.h
@@ -23,7 +23,7 @@ typedef NS_ENUM(NSInteger, ApptentiveConversationState) {
 
 extern NSString *NSStringFromApptentiveConversationState(ApptentiveConversationState state);
 
-@class ApptentivePerson, ApptentiveDevice, ApptentiveSDK, ApptentiveAppRelease, ApptentiveEngagement, ApptentiveVersion, ApptentiveConversationMetadataItem;
+@class ApptentivePerson, ApptentiveDevice, ApptentiveSDK, ApptentiveAppRelease, ApptentiveEngagement, ApptentiveVersion, ApptentiveConversationMetadataItem, ApptentiveRandom;
 @protocol ApptentiveConversationDelegate;
 
 /**
@@ -71,6 +71,11 @@ extern NSString *NSStringFromApptentiveConversationState(ApptentiveConversationS
  */
 @property (readonly, nonatomic) ApptentiveEngagement *engagement;
 
+/**
+ The `ApptentiveRandom` object for this conversation.
+ */
+@property (readonly, nonatomic) ApptentiveRandom *random;
+
 /**
  The authorization token obtained when creating the conversation.
  */
diff --git a/Apptentive/Apptentive/Engagement/Model/ApptentiveConversation.m b/Apptentive/Apptentive/Engagement/Model/ApptentiveConversation.m
index 9ff8508d5..35527d5d8 100644
--- a/Apptentive/Apptentive/Engagement/Model/ApptentiveConversation.m
+++ b/Apptentive/Apptentive/Engagement/Model/ApptentiveConversation.m
@@ -16,6 +16,7 @@
 #import "ApptentiveUtilities.h"
 #import "ApptentiveVersion.h"
 #import "ApptentiveUnarchiver.h"
+#import "ApptentiveRandom.h"
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -24,6 +25,7 @@
 static NSString *const PersonKey = @"person";
 static NSString *const DeviceKey = @"device";
 static NSString *const EngagementKey = @"engagement";
+static NSString *const RandomKey = @"random";
 static NSString *const APIKeyKey = @"APIKey";
 static NSString *const TokenKey = @"token";
 static NSString *const LegacyTokenKey = @"legacyToken";
@@ -77,6 +79,7 @@ @interface ApptentiveConversation ()
 @property (strong, nonatomic) ApptentivePerson *person;
 @property (strong, nonatomic) ApptentiveDevice *device;
 @property (strong, nonatomic) ApptentiveEngagement *engagement;
+@property (strong, nonatomic) ApptentiveRandom *random;
 @property (strong, nonatomic) NSMutableDictionary *mutableUserInfo;
 @property (strong, nonatomic) NSDictionary *lastSentPerson;
 @property (strong, nonatomic) NSDictionary *lastSentDevice;
@@ -102,6 +105,7 @@ - (instancetype)initWithState:(ApptentiveConversationState)state {
 		_person = [[ApptentivePerson alloc] init];
 		_device = [[ApptentiveDevice alloc] initWithCurrentDevice];
 		_engagement = [[ApptentiveEngagement alloc] init];
+		_random = [[ApptentiveRandom alloc] init];
 		_mutableUserInfo = [[NSMutableDictionary alloc] init];
 
 		_directoryName = [NSUUID UUID].UUIDString;
@@ -120,6 +124,7 @@ - (nullable instancetype)initWithCoder:(NSCoder *)coder {
 		_person = [coder decodeObjectOfClass:[ApptentivePerson class] forKey:PersonKey];
 		_device = [coder decodeObjectOfClass:[ApptentiveDevice class] forKey:DeviceKey];
 		_engagement = [coder decodeObjectOfClass:[ApptentiveEngagement class] forKey:EngagementKey];
+		_random = [coder decodeObjectOfClass:[ApptentiveRandom class] forKey:RandomKey] ?: [[ApptentiveRandom alloc] init];
 		_token = [coder decodeObjectOfClass:[NSString class] forKey:TokenKey];
 		_legacyToken = [coder decodeObjectOfClass:[NSString class] forKey:LegacyTokenKey];
 		_lastMessageID = [coder decodeObjectOfClass:[NSString class] forKey:LastMessageIDKey];
@@ -128,7 +133,7 @@ - (nullable instancetype)initWithCoder:(NSCoder *)coder {
 		_localIdentifier = [coder decodeObjectOfClass:[NSString class] forKey:LocalIdentifierKey] ?: [[NSUUID UUID] UUIDString];
 		_directoryName = [coder decodeObjectOfClass:[NSString class] forKey:DirectoryNameKey];
 
-		NSSet *allowedClasses = [NSSet setWithArray:@[[NSDictionary class], [NSString class]]];
+		NSSet *allowedClasses = [NSSet setWithArray:@[[NSDictionary class], [NSString class], [NSNumber class]]];
 		_lastSentDevice = [coder decodeObjectOfClasses:allowedClasses forKey:LastSentDeviceKey];
 		_lastSentPerson = [coder decodeObjectOfClasses:allowedClasses forKey:LastSentPersonKey];
 	}
@@ -142,6 +147,7 @@ - (void)encodeWithCoder:(NSCoder *)coder {
 	[coder encodeObject:self.person forKey:PersonKey];
 	[coder encodeObject:self.device forKey:DeviceKey];
 	[coder encodeObject:self.engagement forKey:EngagementKey];
+	[coder encodeObject:self.random	forKey:RandomKey];
 	[coder encodeObject:self.token forKey:TokenKey];
 	[coder encodeObject:self.legacyToken forKey:LegacyTokenKey];
 	[coder encodeObject:self.lastMessageID forKey:LastMessageIDKey];
@@ -336,7 +342,7 @@ - (instancetype)initAndMigrate {
 		NSData *lastSentPersondata = [[NSUserDefaults standardUserDefaults] dataForKey:ATPersonLastUpdateValuePreferenceKey];
 
 		if (lastSentPersondata != nil) {
-			NSSet *allowedClasses = [NSSet setWithArray:@[[NSDictionary class], [NSString class]]];
+			NSSet *allowedClasses = [NSSet setWithArray:@[[NSDictionary class], [NSString class], [NSNumber class]]];
             NSDictionary *person = [ApptentiveUnarchiver unarchivedObjectOfClasses:allowedClasses fromData:lastSentPersondata];
 			if ([person isKindOfClass:[NSDictionary class]]) {
 				_lastSentPerson = person[@"person"];
@@ -477,6 +483,7 @@ - (id)mutableCopy {
 	result.person = self.person;
 	result.device = self.device;
 	result.engagement = self.engagement;
+	result.random = self.random;
 	result.mutableUserInfo = self.mutableUserInfo;
 	result.lastSentPerson = self.lastSentPerson;
 	result.lastSentDevice = self.lastSentDevice;
@@ -545,6 +552,7 @@ @implementation ApptentiveMutableConversation
 @dynamic person;
 @dynamic device;
 @dynamic engagement;
+@dynamic random;
 @dynamic token;
 @dynamic identifier;
 @dynamic localIdentifier;
@@ -605,6 +613,8 @@ - (nullable NSObject *)valueForFieldWithPath:(NSString *)path {
 			return [self.person valueForFieldWithPath:rest];
 		} else if ([first isEqualToString:@"device"]) {
 			return [self.device valueForFieldWithPath:rest];
+		} else if ([first isEqualToString:@"random"]) {
+			return [self.random valueForFieldWithPath:rest];
 		}
 	}
 
@@ -639,6 +649,8 @@ - (NSString *)descriptionForFieldWithPath:(id)path {
 			return [self.person descriptionForFieldWithPath:rest];
 		} else if ([first isEqualToString:@"device"]) {
 			return [self.device descriptionForFieldWithPath:rest];
+		} else if ([first isEqualToString:@"random"]) {
+			return [self.random descriptionForFieldWithPath:rest];
 		}
 	}
 
diff --git a/Apptentive/Apptentive/Engagement/Model/ApptentiveConversationManager.m b/Apptentive/Apptentive/Engagement/Model/ApptentiveConversationManager.m
index 5c73f2914..17efed853 100644
--- a/Apptentive/Apptentive/Engagement/Model/ApptentiveConversationManager.m
+++ b/Apptentive/Apptentive/Engagement/Model/ApptentiveConversationManager.m
@@ -1092,6 +1092,7 @@ - (void)updateMissingTimeAtInstall {
 
 		if (timeAtInstall == nil) {
 			ApptentiveLogError(ApptentiveLogTagConversation, @"Error retrieving support directory creation date.");
+			return;
 		}
 
 		[self.activeConversation.appRelease updateMissingTimeAtInstallTo:timeAtInstall];
@@ -1119,6 +1120,7 @@ - (void)setLocalEngagementManifestURL:(NSURL *)localEngagementManifestURL {
 
 			if (!manifestDictionary) {
 				ApptentiveLogError(ApptentiveLogTagConversation, @"Unable to parse local manifest %@ (%@).", localEngagementManifestURL.absoluteString, error);
+				return;
 			}
 
 			_manifest = [[ApptentiveEngagementManifest alloc] initWithJSONDictionary:manifestDictionary cacheLifetime:MAXFLOAT];
diff --git a/Apptentive/Apptentive/Engagement/Model/ApptentiveCustomData.m b/Apptentive/Apptentive/Engagement/Model/ApptentiveCustomData.m
index c2efe485b..e9bb1bf64 100644
--- a/Apptentive/Apptentive/Engagement/Model/ApptentiveCustomData.m
+++ b/Apptentive/Apptentive/Engagement/Model/ApptentiveCustomData.m
@@ -47,7 +47,7 @@ - (nullable instancetype)initWithCoder:(NSCoder *)aDecoder {
 	self = [super initWithCoder:aDecoder];
 
 	if (self) {
-		NSSet *allowedClasses = [NSSet setWithArray:@[[NSDictionary class], [NSString class]]];
+		NSSet *allowedClasses = [NSSet setWithArray:@[[NSDictionary class], [NSString class], [NSNumber class]]];
 		_mutableCustomData = [aDecoder decodeObjectOfClasses:allowedClasses forKey:CustomDataKey];
 		_identifier = [aDecoder decodeObjectOfClass:[NSString class] forKey:IdentifierKey];
 	}
diff --git a/Apptentive/Apptentive/Engagement/Model/ApptentiveDevice.m b/Apptentive/Apptentive/Engagement/Model/ApptentiveDevice.m
index e39606995..012109cc6 100644
--- a/Apptentive/Apptentive/Engagement/Model/ApptentiveDevice.m
+++ b/Apptentive/Apptentive/Engagement/Model/ApptentiveDevice.m
@@ -9,8 +9,6 @@
 #import "ApptentiveDevice.h"
 #import "ApptentiveVersion.h"
 
-#import <CoreTelephony/CTCarrier.h>
-#import <CoreTelephony/CTTelephonyNetworkInfo.h>
 #import <UIKit/UIKit.h>
 #include <stdlib.h>
 #import <sys/sysctl.h>
diff --git a/Apptentive/Apptentive/Engagement/Model/ApptentiveEngagement.m b/Apptentive/Apptentive/Engagement/Model/ApptentiveEngagement.m
index 463557759..439ebd727 100644
--- a/Apptentive/Apptentive/Engagement/Model/ApptentiveEngagement.m
+++ b/Apptentive/Apptentive/Engagement/Model/ApptentiveEngagement.m
@@ -54,10 +54,10 @@ - (instancetype)init {
 - (nullable instancetype)initWithCoder:(NSCoder *)coder {
 	self = [super initWithCoder:coder];
 	if (self) {
-		NSSet *classes = [NSSet setWithArray:@[[NSMutableDictionary class], [ApptentiveCount class]]];
+        NSSet *allowedClasses = [NSSet setWithArray:@[[NSMutableDictionary class], [ApptentiveCount class], [NSString class]]];
 
-		_mutableInteractions = [coder decodeObjectOfClasses:classes forKey:InteractionsKey];
-		_mutableCodePoints = [coder decodeObjectOfClasses:classes forKey:CodePointsKey];
+		_mutableInteractions = [coder decodeObjectOfClasses:allowedClasses forKey:InteractionsKey];
+		_mutableCodePoints = [coder decodeObjectOfClasses:allowedClasses forKey:CodePointsKey];
 		if ([coder containsValueForKey:VersionKey]) {
 			_version = [coder decodeIntegerForKey:VersionKey];
 		} else {
diff --git a/Apptentive/Apptentive/Engagement/Model/ApptentiveEngagementManifest.m b/Apptentive/Apptentive/Engagement/Model/ApptentiveEngagementManifest.m
index a931f93b1..5ba348dce 100644
--- a/Apptentive/Apptentive/Engagement/Model/ApptentiveEngagementManifest.m
+++ b/Apptentive/Apptentive/Engagement/Model/ApptentiveEngagementManifest.m
@@ -102,7 +102,7 @@ - (nullable instancetype)initWithCoder:(NSCoder *)coder {
 
 	if (self) {
 		_targets = [coder decodeObjectOfClass:[ApptentiveTargets class] forKey:TargetsKey];
-		NSSet *allowedClasses = [NSSet setWithArray:@[[NSDictionary class], [ApptentiveInteraction class]]];
+		NSSet *allowedClasses = [NSSet setWithArray:@[[NSDictionary class], [ApptentiveInteraction class], [NSString class]]];
 		_interactions = [coder decodeObjectOfClasses:allowedClasses forKey:InteractionsKey];
 		_expiry = [coder decodeObjectOfClass:[NSDate class] forKey:ExpiryKey];
 	}
diff --git a/Apptentive/Apptentive/Engagement/Model/ApptentiveInteraction.m b/Apptentive/Apptentive/Engagement/Model/ApptentiveInteraction.m
index 2ca7a8981..88a32b0d3 100644
--- a/Apptentive/Apptentive/Engagement/Model/ApptentiveInteraction.m
+++ b/Apptentive/Apptentive/Engagement/Model/ApptentiveInteraction.m
@@ -68,9 +68,9 @@ - (nullable instancetype)initWithCoder:(NSCoder *)coder {
 		self.identifier = [coder decodeObjectOfClass:[NSString class] forKey:@"identifier"];
 		self.priority = [coder decodeIntegerForKey:@"priority"];
 		self.type = [coder decodeObjectOfClass:[NSString class] forKey:@"type"];
-		NSSet *allowedClasses = [NSSet setWithArray:@[[NSDictionary class], [NSString class], [NSArray class]]];
+		NSSet *allowedClasses = [NSSet setWithArray:@[[NSDictionary class], [NSString class], [NSArray class], [NSNumber class]]];
 		self.configuration = [coder decodeObjectOfClasses:allowedClasses forKey:@"configuration"];
-		self.version = [coder decodeObjectOfClass:[NSString class] forKey:@"version"];
+		self.version = [coder decodeObjectOfClass:[NSNumber class] forKey:@"version"];
 	}
 	return self;
 }
diff --git a/Apptentive/Apptentive/Engagement/Model/ApptentiveRandom.h b/Apptentive/Apptentive/Engagement/Model/ApptentiveRandom.h
new file mode 100644
index 000000000..1c161d9a9
--- /dev/null
+++ b/Apptentive/Apptentive/Engagement/Model/ApptentiveRandom.h
@@ -0,0 +1,19 @@
+//
+//  ApptentiveRandom.h
+//  Apptentive
+//
+//  Created by Frank Schmitt on 6/21/21.
+//  Copyright © 2021 Apptentive, Inc. All rights reserved.
+//
+
+#import "ApptentiveState.h"
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface ApptentiveRandom : ApptentiveState
+
+@property (readonly, assign) double newRandomValue;
+
+@end
+
+NS_ASSUME_NONNULL_END
diff --git a/Apptentive/Apptentive/Engagement/Model/ApptentiveRandom.m b/Apptentive/Apptentive/Engagement/Model/ApptentiveRandom.m
new file mode 100644
index 000000000..b7ec8cf59
--- /dev/null
+++ b/Apptentive/Apptentive/Engagement/Model/ApptentiveRandom.m
@@ -0,0 +1,110 @@
+//
+//  ApptentiveRandom.m
+//  Apptentive
+//
+//  Created by Frank Schmitt on 6/21/21.
+//  Copyright © 2021 Apptentive, Inc. All rights reserved.
+//
+
+#import "ApptentiveRandom.h"
+
+static NSString *const RandomValuesKey = @"random_values";
+
+@interface ApptentiveRandom ()
+
+@property (strong, nonatomic) NSMutableDictionary<NSString *, NSNumber *> *randomValues;
+
+@end
+
+@implementation ApptentiveRandom
+
++ (BOOL)supportsSecureCoding {
+	return YES;
+}
+
+- (instancetype)init {
+	self = [super init];
+	if (self) {
+		_randomValues = [NSMutableDictionary dictionary];
+	}
+	return self;
+}
+
+- (nullable instancetype)initWithCoder:(NSCoder *)coder {
+	self = [super initWithCoder:coder];
+	if (self) {
+		_randomValues = [coder decodeObjectOfClass:[NSMutableDictionary class] forKey:RandomValuesKey];
+	}
+	return self;
+}
+
+- (void)encodeWithCoder:(NSCoder *)coder {
+	[super encodeWithCoder:coder];
+	[coder encodeObject:self.randomValues forKey:RandomValuesKey];
+}
+
+#pragma mark - Targeting State
+
+- (NSObject *)valueForFieldWithPath:(NSString *)path {
+	NSArray *parts = [path componentsSeparatedByString:@"/"];
+
+	if (parts.count > 0 && parts.count <= 2 && [parts.lastObject isEqualToString:@"percent"]) {
+		NSString *key = parts.count == 2 ? parts[0] : nil;
+
+		return @([self randomPercentForKey:key]);
+	} else {
+		ApptentiveLogError(@"Unrecognized field name “%@”", path);
+		return nil;
+	}
+}
+
+- (NSString *)descriptionForFieldWithPath:(NSString *)path {
+	NSArray *parts = [path componentsSeparatedByString:@"/"];
+
+	if (parts.count > 0 && parts.count <= 2 && [parts.lastObject isEqualToString:@"percent"]) {
+		NSString *key = parts.count == 2 ? parts[0] : nil;
+
+		return [self descriptionOfPercentForKey:key];
+	} else {
+		return [NSString stringWithFormat:@"Unrecognized engagement field %@", path];
+	}
+}
+
+#pragma mark - Private
+
+- (NSString *)descriptionOfPercentForKey:(nullable NSString *)key {
+	if (key == nil) {
+		return @"Random percentage";
+	} else if (self.randomValues[key] == nil) {
+		return [NSString stringWithFormat:@"Random percentage that will be saved for key “%@”", key];
+	} else {
+		return [NSString stringWithFormat:@"Random percentage that was saved for key “%@”", key];
+	}
+}
+
+- (double)randomPercentForKey:(nullable NSString *)key {
+	return [self randomValueForKey:key] * 100.0;
+}
+
+- (double)randomValueForKey:(nullable NSString *)key {
+	if (key == nil) {
+		return self.newRandomValue;
+	} else {
+		if (self.randomValues[key] == nil) {
+			self.randomValues[key] = @(self.newRandomValue);
+		}
+
+		return self.randomValues[key].doubleValue;
+	}
+}
+
+- (double)newRandomValue {
+#if APPTENTIVE_DEBUG
+	ApptentiveLogInfo(@"Note: all random sampling percentages will be assigned/saved as 50% when running debug build.");
+	return 0.5;
+#else
+	return (double)arc4random() / UINT32_MAX;
+#endif
+}
+
+@end
diff --git a/Apptentive/Apptentive/Engagement/Model/Targeting/ApptentiveComparisonClause.m b/Apptentive/Apptentive/Engagement/Model/Targeting/ApptentiveComparisonClause.m
index 7b8daba8c..3234bd7b1 100644
--- a/Apptentive/Apptentive/Engagement/Model/Targeting/ApptentiveComparisonClause.m
+++ b/Apptentive/Apptentive/Engagement/Model/Targeting/ApptentiveComparisonClause.m
@@ -148,7 +148,7 @@ - (nullable instancetype)initWithCoder:(NSCoder *)coder
 	self = [super init];
 	if (self) {
 		_field = [coder decodeObjectOfClass:[NSString class] forKey:FieldKey];
-		NSSet *allowedClasses = [NSSet setWithArray:@[[NSDictionary class], [NSString class]]];
+		NSSet *allowedClasses = [NSSet setWithArray:@[[NSDictionary class], [NSString class], [NSNumber class]]];
 		_comparisons = [coder decodeObjectOfClasses:allowedClasses forKey:ComparisonsKey];
 	}
 	return self;
diff --git a/Apptentive/Apptentive/Engagement/Model/Targeting/ApptentiveTargets.m b/Apptentive/Apptentive/Engagement/Model/Targeting/ApptentiveTargets.m
index ec864016f..0ec83b39a 100644
--- a/Apptentive/Apptentive/Engagement/Model/Targeting/ApptentiveTargets.m
+++ b/Apptentive/Apptentive/Engagement/Model/Targeting/ApptentiveTargets.m
@@ -49,7 +49,7 @@ - (nullable instancetype)initWithCoder:(NSCoder *)coder
 {
 	self = [super init];
 	if (self) {
-		NSSet *allowedClasses = [NSSet setWithArray:@[[NSDictionary class], [ApptentiveInvocations class]]];
+		NSSet *allowedClasses = [NSSet setWithArray:@[[NSDictionary class], [ApptentiveInvocations class], [NSString class]]];
 		_invocations = [coder decodeObjectOfClasses:allowedClasses forKey:InvocationsKey];
 	}
 	return self;
diff --git a/Apptentive/Apptentive/Info.plist b/Apptentive/Apptentive/Info.plist
index cf543d82c..b5c597653 100644
--- a/Apptentive/Apptentive/Info.plist
+++ b/Apptentive/Apptentive/Info.plist
@@ -15,7 +15,7 @@
 	<key>CFBundlePackageType</key>
 	<string>FMWK</string>
 	<key>CFBundleShortVersionString</key>
-	<string>5.3.3</string>
+	<string>5.3.4</string>
 	<key>CFBundleVersion</key>
 	<string>$(CURRENT_PROJECT_VERSION)</string>
 	<key>NSPrincipalClass</key>
diff --git a/Apptentive/Apptentive/Message Center/ApptentiveMessageCenterViewModel.h b/Apptentive/Apptentive/Message Center/ApptentiveMessageCenterViewModel.h
index a7f394ff2..9b15ab1d4 100644
--- a/Apptentive/Apptentive/Message Center/ApptentiveMessageCenterViewModel.h	
+++ b/Apptentive/Apptentive/Message Center/ApptentiveMessageCenterViewModel.h	
@@ -55,7 +55,7 @@ typedef NS_ENUM(NSInteger, ATMessageCenterMessageStatus) {
 
 @property (readonly, nonatomic) NSString *greetingTitle;
 @property (readonly, nonatomic) NSString *greetingBody;
-@property (readonly, nonatomic) NSURL *greetingImageURL;
+@property (readonly, nonatomic, nullable) NSURL *greetingImageURL;
 
 @property (readonly, nonatomic) NSString *statusBody;
 
diff --git a/Apptentive/Apptentive/Message Center/ApptentiveMessageCenterViewModel.m b/Apptentive/Apptentive/Message Center/ApptentiveMessageCenterViewModel.m
index 07a6bfdb5..e93560144 100644
--- a/Apptentive/Apptentive/Message Center/ApptentiveMessageCenterViewModel.m	
+++ b/Apptentive/Apptentive/Message Center/ApptentiveMessageCenterViewModel.m	
@@ -141,7 +141,7 @@ - (NSString *)greetingBody {
 	return self.interaction.configuration[@"greeting"][@"body"];
 }
 
-- (NSURL *)greetingImageURL {
+- (nullable NSURL *)greetingImageURL {
 	NSString *URLString = self.interaction.configuration[@"greeting"][@"image_url"];
 
 	return (URLString.length > 0) ? [NSURL URLWithString:URLString] : nil;
diff --git a/Apptentive/Apptentive/Message Center/Model/ApptentiveMessageManager.h b/Apptentive/Apptentive/Message Center/Model/ApptentiveMessageManager.h
index cf5e5966c..e51a6da26 100644
--- a/Apptentive/Apptentive/Message Center/Model/ApptentiveMessageManager.h	
+++ b/Apptentive/Apptentive/Message Center/Model/ApptentiveMessageManager.h	
@@ -58,7 +58,7 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (void)updateUnreadCount;
 
-+ (NSString *)attachmentDirectoryPathForConversationDirectory:(NSString *)storagePath;
++ (nullable NSString *)attachmentDirectoryPathForConversationDirectory:(NSString *)storagePath;
 
 @property (readonly, nonatomic) NSString *attachmentDirectoryPath;
 
diff --git a/Apptentive/Apptentive/Message Center/Model/ApptentiveMessageManager.m b/Apptentive/Apptentive/Message Center/Model/ApptentiveMessageManager.m
index af0f6e8ab..60690244a 100644
--- a/Apptentive/Apptentive/Message Center/Model/ApptentiveMessageManager.m	
+++ b/Apptentive/Apptentive/Message Center/Model/ApptentiveMessageManager.m	
@@ -156,7 +156,7 @@ - (NSString *)attachmentDirectoryPath {
 	return [[self class] attachmentDirectoryPathForConversationDirectory:self.storagePath];
 }
 
-+ (NSString *)attachmentDirectoryPathForConversationDirectory:(NSString *)conversationDirectory {
++ (nullable NSString *)attachmentDirectoryPathForConversationDirectory:(NSString *)conversationDirectory {
 	NSString *result = [conversationDirectory stringByAppendingPathComponent:@"Attachments"];
 
 	if (![[NSFileManager defaultManager] fileExistsAtPath:result]) {
diff --git a/Apptentive/Apptentive/Message Center/Model/ApptentiveMessageStore.m b/Apptentive/Apptentive/Message Center/Model/ApptentiveMessageStore.m
index 426d9a293..badc092c1 100644
--- a/Apptentive/Apptentive/Message Center/Model/ApptentiveMessageStore.m	
+++ b/Apptentive/Apptentive/Message Center/Model/ApptentiveMessageStore.m	
@@ -33,7 +33,7 @@ - (instancetype)init {
 - (nullable instancetype)initWithCoder:(NSCoder *)coder {
 	self = [super init];
 	if (self) {
-		NSSet *allowedClasses = [NSSet setWithArray:@[[NSArray class], [ApptentiveMessage class]]];
+		NSSet *allowedClasses = [NSSet setWithArray:@[[NSMutableArray class], [ApptentiveMessage class]]];
 		_messages = [coder decodeObjectOfClasses:allowedClasses forKey:MessagesKey];
 		_lastMessageIdentifier = [coder decodeObjectOfClass:[NSString class] forKey:LastMessageIdentifierKey];
 	}
diff --git a/Apptentive/Apptentive/Misc/ApptentiveArchiver.h b/Apptentive/Apptentive/Misc/ApptentiveArchiver.h
index 1034999b5..9897f2f49 100644
--- a/Apptentive/Apptentive/Misc/ApptentiveArchiver.h
+++ b/Apptentive/Apptentive/Misc/ApptentiveArchiver.h
@@ -13,7 +13,7 @@ NS_ASSUME_NONNULL_BEGIN
 @interface ApptentiveArchiver : NSObject
 
 + (BOOL)archiveRootObject:(NSObject *)rootObject toFile:(NSString *)path;
-+ (NSData *)archivedDataWithRootObject:(NSObject *)rootObject;
++ (nullable NSData *)archivedDataWithRootObject:(NSObject *)rootObject;
 
 @end
 
diff --git a/Apptentive/Apptentive/Misc/ApptentiveArchiver.m b/Apptentive/Apptentive/Misc/ApptentiveArchiver.m
index b8cb33e4a..71fb74a64 100644
--- a/Apptentive/Apptentive/Misc/ApptentiveArchiver.m
+++ b/Apptentive/Apptentive/Misc/ApptentiveArchiver.m
@@ -20,7 +20,7 @@ + (BOOL)archiveRootObject:(NSObject *)rootObject toFile:(NSString *)path {
 	}
 }
 
-+ (NSData *)archivedDataWithRootObject:(NSObject *)rootObject {
++ (nullable NSData *)archivedDataWithRootObject:(NSObject *)rootObject {
 	NSError *error = nil;
 	NSData *result = nil;
 
diff --git a/Apptentive/Apptentive/Misc/ApptentiveLog.h b/Apptentive/Apptentive/Misc/ApptentiveLog.h
index 8a4ec9066..2258622b3 100644
--- a/Apptentive/Apptentive/Misc/ApptentiveLog.h
+++ b/Apptentive/Apptentive/Misc/ApptentiveLog.h
@@ -40,7 +40,7 @@ void ApptentiveLogInfo(id arg, ...);
 void ApptentiveLogDebug(id arg, ...);
 void ApptentiveLogVerbose(id arg, ...);
 
-void ApptentiveStartLogMonitor(NSString *logDir);
+void ApptentiveStartLogWriter(NSString *logDir);
 NSArray<NSString *> * _Nullable ApptentiveListLogFiles(void);
 
 NS_ASSUME_NONNULL_END
diff --git a/Apptentive/Apptentive/Misc/ApptentiveLog.m b/Apptentive/Apptentive/Misc/ApptentiveLog.m
index 8dfdae9f6..7a094fed1 100644
--- a/Apptentive/Apptentive/Misc/ApptentiveLog.m
+++ b/Apptentive/Apptentive/Misc/ApptentiveLog.m
@@ -194,7 +194,7 @@ void setShouldSanitizeApptentiveLogMessages(BOOL shouldSanitize) {
 	_shouldSanitizeLogMessages = shouldSanitize;
 }
 
-void ApptentiveStartLogMonitor(NSString *logDir) {
+void ApptentiveStartLogWriter(NSString *logDir) {
 	_logWriter = [[ApptentiveAsyncLogWriter alloc] initWithDestDir:logDir historySize:kLogHistorySize];
 }
 
diff --git a/Apptentive/Apptentive/Misc/ApptentiveLogMonitor.m b/Apptentive/Apptentive/Misc/ApptentiveLogMonitor.m
index 77913c2b2..4e0254c0a 100644
--- a/Apptentive/Apptentive/Misc/ApptentiveLogMonitor.m
+++ b/Apptentive/Apptentive/Misc/ApptentiveLogMonitor.m
@@ -240,24 +240,31 @@ + (BOOL)IsMobileConfigInstalled {
     SecPolicyRef policy = SecPolicyCreateBasicX509();
     SecTrustRef trust;
 
-    OSStatus err = SecTrustCreateWithCertificates((__bridge CFArrayRef) [NSArray arrayWithObject:(__bridge id)cert], policy, &trust);
+    OSStatus status = SecTrustCreateWithCertificates((__bridge CFArrayRef) [NSArray arrayWithObject:(__bridge id)cert], policy, &trust);
+    if (status != 0) {
+        ApptentiveLogInfo(@"OSStatus is %d.", status);
+    }
 
 	BOOL result = NO;
 
 	if (@available(iOS 12.0, *)) {
 		CFErrorRef trustError = NULL;
 
-		err = SecTrustEvaluateWithError(trust, &trustError);
+		status = SecTrustEvaluateWithError(trust, &trustError);
 
 		result = (trustError == nil);
 	} else {
 		SecTrustResultType trustResult = -1;
 
-		err = SecTrustEvaluate(trust, &trustResult);
+		status = SecTrustEvaluate(trust, &trustResult);
 
 		result = (trustResult == kSecTrustResultUnspecified || trustResult == kSecTrustResultProceed);
 	}
 
+    if (status != 0) {
+        ApptentiveLogInfo(@"OSStatus is %d.", status);
+    }
+
     CFRelease(trust);
     CFRelease(policy);
     CFRelease(cert);
diff --git a/Apptentive/Apptentive/Misc/ApptentiveLogMonitorSession.m b/Apptentive/Apptentive/Misc/ApptentiveLogMonitorSession.m
index 4b269d639..9c107d56e 100644
--- a/Apptentive/Apptentive/Misc/ApptentiveLogMonitorSession.m
+++ b/Apptentive/Apptentive/Misc/ApptentiveLogMonitorSession.m
@@ -15,6 +15,7 @@
 #import "ApptentiveSafeCollections.h"
 #import "ApptentiveArchiver.h"
 #import "ApptentiveUnarchiver.h"
+#import "UIWindow+Apptentive.h"
 
 NSNotificationName const ApptentiveLogMonitorSessionDidStart = @"ApptentiveLogMonitorSessionDidStart";
 NSNotificationName const ApptentiveLogMonitorSessionDidStop = @"ApptentiveLogMonitorSessionDidStop";
@@ -27,7 +28,7 @@
 
 @interface ApptentiveLogMonitorSession () <NSSecureCoding, MFMailComposeViewControllerDelegate>
 
-@property (nonatomic, strong) UIWindow *mailComposeControllerWindow;
+@property (nonatomic, strong) UIWindow *presentationWindow;
 @property (nonatomic, assign) ApptentiveLogLevel oldLogLevel;
 
 @end
@@ -64,7 +65,9 @@ - (void)start {
 	ApptentiveLogSetLevel(ApptentiveLogLevelVerbose);
 	
 	dispatch_async(dispatch_get_main_queue(), ^{
-		[self showReportUI];
+		if (self.presentationWindow == nil) {
+			[self showReportUI];
+		}
 	});
 	
 	[[NSNotificationCenter defaultCenter] postNotificationName:ApptentiveLogMonitorSessionDidStart object:nil];
@@ -72,7 +75,9 @@ - (void)start {
 
 - (void)resume {
 	dispatch_async(dispatch_get_main_queue(), ^{
-		[self showReportUI];
+		if (self.presentationWindow == nil) {
+			[self showReportUI];
+		}
 	});
 }
 
@@ -86,91 +91,94 @@ - (void)stop {
 
 - (void)showReportUI {
 	// create a custom window to show UI on top of everything
-	UIWindow *window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
+	self.presentationWindow = [UIWindow apptentive_windowWithRootViewController:[[UIViewController alloc] init]];
 	
 	// create alert controller with "Send", "Continue" and "Discard" actions
 	UIAlertController *alertController = [UIAlertController alertControllerWithTitle:ApptentiveLocalizedString(@"Apptentive", @"Apptentive") message:ApptentiveLocalizedString(@"Troubleshooting mode", @"Troubleshooting mode") preferredStyle:UIAlertControllerStyleActionSheet];
 	[alertController addAction:[UIAlertAction actionWithTitle:ApptentiveLocalizedString(@"Send Report", @"Send Report")
 														style:UIAlertActionStyleDefault
 													  handler:^(UIAlertAction *_Nonnull action) {
-														  window.hidden = YES;
-														  [self sendReportWithAttachedFiles:[ApptentiveLogMonitorSession listAttachments]];
-													  }]];
+		self.presentationWindow.hidden = YES;
+		self.presentationWindow = nil;
+		[self sendReportWithAttachedFiles:[ApptentiveLogMonitorSession listAttachments]];
+	}]];
 	[alertController addAction:[UIAlertAction actionWithTitle:ApptentiveLocalizedString(@"Continue", @"Continue")
 														style:UIAlertActionStyleCancel
 													  handler:^(UIAlertAction *_Nonnull action) {
-														  window.hidden = YES;
-													  }]];
+		self.presentationWindow.hidden = YES;
+		self.presentationWindow = nil;
+	}]];
 	[alertController addAction:[UIAlertAction actionWithTitle:ApptentiveLocalizedString(@"Discard Report", @"Discard Report")
 														style:UIAlertActionStyleDestructive
 													  handler:^(UIAlertAction *_Nonnull action) {
-														  window.hidden = YES;
-														  [self stop];
-													  }]];
+		self.presentationWindow.hidden = YES;
+		self.presentationWindow = nil;
+		[self stop];
+	}]];
 	
-	window.rootViewController = [[UIViewController alloc] init];
-	window.windowLevel = UIWindowLevelAlert + 1;
-	window.hidden = NO; // don't use makeKeyAndVisible since we don't have any knowledge about the host app's UI
-	[window.rootViewController presentViewController:alertController animated:YES completion:nil];
+	self.presentationWindow.hidden = NO; // don't use makeKeyAndVisible since we don't have any knowledge about the host app's UI
+	[self.presentationWindow.rootViewController presentViewController:alertController animated:YES completion:nil];
 }
 
 #pragma mark -
 #pragma mark Report
 
 - (void)sendReportWithAttachedFiles:(NSArray<NSString *> *)files {
-	if (![MFMailComposeViewController canSendMail]) {
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wdeprecated-declarations"
-		UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:ApptentiveLocalizedString(@"Apptentive Log Monitor", @"Apptentive Log Monitor") message:ApptentiveLocalizedString(@"Unable to send email", @"Unable to send email") delegate:nil cancelButtonTitle:ApptentiveLocalizedString(@"OK", @"OK") otherButtonTitles:nil];
-		[alertView show];
-#pragma clang diagnostic pop
-		
-		return;
-	}
-	
-	NSDictionary *bundleInfo = [[NSBundle mainBundle] infoDictionary];
-	
-	// collecting system info
-	NSMutableString *messageBody = [NSMutableString new];
-	[messageBody appendString:@"This email may contain sensitive content.\n Please review before sending.\n\n"];
-	[messageBody appendFormat:@"App Bundle Identifier: %@\n", [NSBundle mainBundle].bundleIdentifier];
-	[messageBody appendFormat:@"App Version: %@\n", [bundleInfo objectForKey:@"CFBundleShortVersionString"]];
-	[messageBody appendFormat:@"App Build: %@\n", [bundleInfo objectForKey:@"CFBundleVersion"]];
-	[messageBody appendFormat:@"Apptentive SDK: %@\n", kApptentiveVersionString];
-	[messageBody appendFormat:@"Device Model: %@\n", [ApptentiveUtilities deviceMachine]];
-	[messageBody appendFormat:@"iOS Version: %@\n", [UIDevice currentDevice].systemVersion];
-	[messageBody appendFormat:@"Locale: %@", [NSLocale currentLocale].localeIdentifier];
-	
-	NSString *emailTitle = [NSString stringWithFormat:@"%@ (iOS)", [NSBundle mainBundle].infoDictionary[@"CFBundleName"]];
-	
-	MFMailComposeViewController *mc = [[MFMailComposeViewController alloc] init];
-	mc.mailComposeDelegate = self;
-	[mc setSubject:emailTitle];
-	[mc setMessageBody:messageBody isHTML:NO];
-	[mc setToRecipients:_emailRecipients];
-	
-	// Get the resource path and read the file using NSData
-	for (NSString *path in files) {
-		NSString *filename = [path lastPathComponent];
-		NSData *fileData = [NSData dataWithContentsOfFile:path];
-		if (fileData.length == 0) {
-			ApptentiveLogError(ApptentiveLogTagMonitor, @"Attachment file does not exist or empty: %@", path);
-			continue;
+	// Present mail view controller/unavailable alert on screen in a separate window
+	UIViewController *presentedViewController = nil;
+
+	self.presentationWindow = [UIWindow apptentive_windowWithRootViewController:[[UIViewController alloc] init]];
+	self.presentationWindow.hidden = NO;
+
+	if ([MFMailComposeViewController canSendMail]) {
+		// collecting system info
+		NSDictionary *bundleInfo = [[NSBundle mainBundle] infoDictionary];
+
+		NSMutableString *messageBody = [NSMutableString new];
+		[messageBody appendString:@"This email may contain sensitive content.\n Please review before sending.\n\n"];
+		[messageBody appendFormat:@"App Bundle Identifier: %@\n", [NSBundle mainBundle].bundleIdentifier];
+		[messageBody appendFormat:@"App Version: %@\n", [bundleInfo objectForKey:@"CFBundleShortVersionString"]];
+		[messageBody appendFormat:@"App Build: %@\n", [bundleInfo objectForKey:@"CFBundleVersion"]];
+		[messageBody appendFormat:@"Apptentive SDK: %@\n", kApptentiveVersionString];
+		[messageBody appendFormat:@"Device Model: %@\n", [ApptentiveUtilities deviceMachine]];
+		[messageBody appendFormat:@"iOS Version: %@\n", [UIDevice currentDevice].systemVersion];
+		[messageBody appendFormat:@"Locale: %@", [NSLocale currentLocale].localeIdentifier];
+
+		NSString *emailTitle = [NSString stringWithFormat:@"%@ (iOS)", [NSBundle mainBundle].infoDictionary[@"CFBundleName"]];
+
+		MFMailComposeViewController *mc = [[MFMailComposeViewController alloc] init];
+		mc.mailComposeDelegate = self;
+		[mc setSubject:emailTitle];
+		[mc setMessageBody:messageBody isHTML:NO];
+		[mc setToRecipients:_emailRecipients];
+
+		// Get the resource path and read the file using NSData
+		for (NSString *path in files) {
+			NSString *filename = [path lastPathComponent];
+			NSData *fileData = [NSData dataWithContentsOfFile:path];
+			if (fileData.length == 0) {
+				ApptentiveLogError(ApptentiveLogTagMonitor, @"Attachment file does not exist or empty: %@", path);
+				continue;
+			}
+
+			// Add attachment
+			[mc addAttachmentData:fileData mimeType:@"text/plain" fileName:filename];
 		}
-		
-		// Add attachment
-		[mc addAttachmentData:fileData mimeType:@"text/plain" fileName:filename];
+
+		presentedViewController = mc;
+	} else {
+		UIAlertController *alertController = [UIAlertController alertControllerWithTitle:ApptentiveLocalizedString(@"Apptentive Log Monitor", @"Apptentive Log Monitor") message:ApptentiveLocalizedString(@"Unable to send email", @"Unable to send email") preferredStyle:UIAlertControllerStyleAlert];
+		[alertController addAction:[UIAlertAction actionWithTitle:ApptentiveLocalizedString(@"OK", @"OK")
+															style:UIAlertActionStyleCancel
+														  handler:^(UIAlertAction *_Nonnull action) {
+			self.presentationWindow.hidden = YES;
+			self.presentationWindow = nil;
+		}]];
+
+		presentedViewController = alertController;
 	}
-	
-	// Present mail view controller on screen in a separate window
-	UIViewController *rootController = [UIViewController new];
-	
-	self.mailComposeControllerWindow = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
-	self.mailComposeControllerWindow.windowLevel = UIWindowLevelAlert + 1;
-	self.mailComposeControllerWindow.rootViewController = rootController;
-	self.mailComposeControllerWindow.hidden = NO;
-	
-	[rootController presentViewController:mc animated:YES completion:nil];
+
+	[self.presentationWindow.rootViewController presentViewController:presentedViewController animated:YES completion:nil];
 }
 
 #pragma mark -
@@ -180,8 +188,8 @@ - (void)mailComposeController:(MFMailComposeViewController *)controller didFinis
 	[controller dismissViewControllerAnimated:YES
 								   completion:^{
 									   [self stop];
-									   self.mailComposeControllerWindow.hidden = YES;
-									   self.mailComposeControllerWindow = nil;
+									   self.presentationWindow.hidden = YES;
+									   self.presentationWindow = nil;
 								   }];
 }
 
diff --git a/Apptentive/Apptentive/Misc/ApptentiveStoreProductViewController.m b/Apptentive/Apptentive/Misc/ApptentiveStoreProductViewController.m
index 6ffebd325..f5f78a41e 100644
--- a/Apptentive/Apptentive/Misc/ApptentiveStoreProductViewController.m
+++ b/Apptentive/Apptentive/Misc/ApptentiveStoreProductViewController.m
@@ -7,6 +7,7 @@
 //
 
 #import "ApptentiveStoreProductViewController.h"
+#import "UIWindow+Apptentive.h"
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -21,9 +22,7 @@ @interface ApptentiveStoreProductViewController ()
 @implementation ApptentiveStoreProductViewController
 
 - (void)presentAnimated:(BOOL)animated completion:(void (^__nullable)(void))completion {
-	self.apptentiveAlertWindow = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
-	self.apptentiveAlertWindow.rootViewController = [[UIViewController alloc] init];
-	self.apptentiveAlertWindow.windowLevel = UIWindowLevelAlert + 1;
+	self.apptentiveAlertWindow = [UIWindow apptentive_windowWithRootViewController:[[UIViewController alloc] init]];
 	[self.apptentiveAlertWindow makeKeyAndVisible];
 	[self.apptentiveAlertWindow.rootViewController presentViewController:self animated:animated completion:completion];
 }
diff --git a/Apptentive/Apptentive/Misc/ApptentiveUtilities.h b/Apptentive/Apptentive/Misc/ApptentiveUtilities.h
index 727ca5f90..f3d845a2b 100644
--- a/Apptentive/Apptentive/Misc/ApptentiveUtilities.h
+++ b/Apptentive/Apptentive/Misc/ApptentiveUtilities.h
@@ -12,8 +12,8 @@ NS_ASSUME_NONNULL_BEGIN
 
 
 @interface ApptentiveUtilities : NSObject
-+ (NSString *)applicationSupportPath;
-+ (NSString * _Nullable)cacheDirectoryPath:(NSString *)path;
++ (nullable NSString *)applicationSupportPath;
++ (nullable NSString *)cacheDirectoryPath:(NSString *)path;
 + (NSBundle *)resourceBundle;
 + (UIStoryboard *)storyboard;
 + (UIImage *)imageNamed:(NSString *)name;
diff --git a/Apptentive/Apptentive/Misc/ApptentiveUtilities.m b/Apptentive/Apptentive/Misc/ApptentiveUtilities.m
index ab3bc8539..e9505f817 100644
--- a/Apptentive/Apptentive/Misc/ApptentiveUtilities.m
+++ b/Apptentive/Apptentive/Misc/ApptentiveUtilities.m
@@ -31,25 +31,27 @@
 
 @implementation ApptentiveUtilities
 
-+ (NSString *)applicationSupportPath {
++ (nullable NSString *)applicationSupportPath {
 	static NSString *_applicationSupportPath;
 	static dispatch_once_t onceToken;
 	dispatch_once(&onceToken, ^{
-	  _applicationSupportPath = NSSearchPathForDirectoriesInDomains(NSApplicationSupportDirectory, NSUserDomainMask, YES).firstObject;
-
-	  NSError *error;
+		_applicationSupportPath = NSSearchPathForDirectoriesInDomains(NSApplicationSupportDirectory, NSUserDomainMask, YES).firstObject;
+		NSError *error;
 
-	  if (![[NSFileManager defaultManager] createDirectoryAtPath:_applicationSupportPath withIntermediateDirectories:YES attributes:nil error:&error]) {
-		  ApptentiveLogError(ApptentiveLogTagUtility, @"Failed to create Application Support directory: %@", _applicationSupportPath);
-		  ApptentiveLogError(ApptentiveLogTagUtility, @"Error was: %@", error);
-		  _applicationSupportPath = nil;
-	  }
+		if (![[NSFileManager defaultManager] createDirectoryAtPath:_applicationSupportPath withIntermediateDirectories:YES attributes:nil error:&error]) {
+			ApptentiveLogError(ApptentiveLogTagUtility, @"Failed to create Application Support directory: %@", _applicationSupportPath);
+			ApptentiveLogError(ApptentiveLogTagUtility, @"Error was: %@", error);
+			_applicationSupportPath = nil;
+		}
 
+		if (_applicationSupportPath == nil) {
+			return;
+		}
 
-	  if (![[NSFileManager defaultManager] setAttributes:@{ NSFileProtectionKey: NSFileProtectionCompleteUntilFirstUserAuthentication } ofItemAtPath:_applicationSupportPath error:&error]) {
-		  ApptentiveLogError(ApptentiveLogTagUtility, @"Failed to set file protection level: %@", _applicationSupportPath);
-		  ApptentiveLogError(ApptentiveLogTagUtility, @"Error was: %@", error);
-	  }
+		if (![[NSFileManager defaultManager] setAttributes:@{ NSFileProtectionKey: NSFileProtectionCompleteUntilFirstUserAuthentication } ofItemAtPath:_applicationSupportPath error:&error]) {
+			ApptentiveLogError(ApptentiveLogTagUtility, @"Failed to set file protection level: %@", _applicationSupportPath);
+			ApptentiveLogError(ApptentiveLogTagUtility, @"Error was: %@", error);
+		}
 	});
 
 	return _applicationSupportPath;
@@ -74,6 +76,10 @@ + (NSString * _Nullable)cacheDirectoryPath:(NSString *)path {
 			_cacheDirectoryPath = nil;
 		}
 		
+		if (_cacheDirectoryPath == nil) {
+			return;
+		}
+
 		if (![[NSFileManager defaultManager] setAttributes:@{ NSFileProtectionKey: NSFileProtectionCompleteUntilFirstUserAuthentication } ofItemAtPath:_cacheDirectoryPath error:&error]) {
 			ApptentiveLogError(ApptentiveLogTagUtility, @"Failed to set file protection level: %@", _cacheDirectoryPath);
 			ApptentiveLogError(ApptentiveLogTagUtility, @"Error was: %@", error);
diff --git a/Apptentive/Apptentive/Misc/UIAlertController+Apptentive.m b/Apptentive/Apptentive/Misc/UIAlertController+Apptentive.m
index 843260d05..cd23a443a 100644
--- a/Apptentive/Apptentive/Misc/UIAlertController+Apptentive.m
+++ b/Apptentive/Apptentive/Misc/UIAlertController+Apptentive.m
@@ -7,6 +7,7 @@
 //
 
 #import "UIAlertController+Apptentive.h"
+#import "UIWindow+Apptentive.h"
 
 #import <objc/runtime.h>
 
@@ -38,9 +39,7 @@ - (nullable UIWindow *)apptentiveAlertWindow {
 @implementation UIAlertController (Apptentive)
 
 - (void)apptentive_presentAnimated:(BOOL)animated completion:(void (^__nullable)(void))completion {
-	self.apptentiveAlertWindow = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
-	self.apptentiveAlertWindow.rootViewController = [[UIViewController alloc] init];
-	self.apptentiveAlertWindow.windowLevel = UIWindowLevelAlert + 1;
+	self.apptentiveAlertWindow = [UIWindow apptentive_windowWithRootViewController:[[UIViewController alloc] init]];
 	[self.apptentiveAlertWindow makeKeyAndVisible];
 	[self.apptentiveAlertWindow.rootViewController presentViewController:self animated:animated completion:completion];
 }
diff --git a/Apptentive/Apptentive/Misc/UIWindow+Apptentive.h b/Apptentive/Apptentive/Misc/UIWindow+Apptentive.h
new file mode 100644
index 000000000..7e0e4e45d
--- /dev/null
+++ b/Apptentive/Apptentive/Misc/UIWindow+Apptentive.h
@@ -0,0 +1,19 @@
+//
+//  UIWindow+Apptentive.h
+//  Apptentive
+//
+//  Created by Frank Schmitt on 7/29/21.
+//  Copyright © 2021 Apptentive, Inc. All rights reserved.
+//
+
+#import <UIKit/UIKit.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface UIWindow (Apptentive)
+
++ (instancetype)apptentive_windowWithRootViewController:(UIViewController *)rootViewController;
+
+@end
+
+NS_ASSUME_NONNULL_END
diff --git a/Apptentive/Apptentive/Misc/UIWindow+Apptentive.m b/Apptentive/Apptentive/Misc/UIWindow+Apptentive.m
new file mode 100644
index 000000000..ac6370568
--- /dev/null
+++ b/Apptentive/Apptentive/Misc/UIWindow+Apptentive.m
@@ -0,0 +1,45 @@
+//
+//  UIWindow+Apptentive.m
+//  Apptentive
+//
+//  Created by Frank Schmitt on 7/29/21.
+//  Copyright © 2021 Apptentive, Inc. All rights reserved.
+//
+
+#import "UIWindow+Apptentive.h"
+
+@implementation UIWindow (Apptentive)
+
++ (instancetype)apptentive_windowWithRootViewController:(UIViewController *)rootViewController {
+	UIWindow *window;
+	
+	if (@available(iOS 13.0, *)) {
+		// Look for an active foreground scene.
+		for (UIScene *scene in UIApplication.sharedApplication.connectedScenes.allObjects) {
+			if ([scene isKindOfClass:[UIWindowScene class]] && scene.activationState == UISceneActivationStateForegroundActive) {
+				window = [[self alloc] initWithWindowScene:(UIWindowScene *)scene];
+			}
+		}
+		
+		if (window == nil) {
+			// Settle for an inactive foreground scene.
+			for (UIScene *scene in UIApplication.sharedApplication.connectedScenes.allObjects) {
+				if ([scene isKindOfClass:[UIWindowScene class]] && scene.activationState == UISceneActivationStateForegroundInactive) {
+					window = [[self alloc] initWithWindowScene:(UIWindowScene *)scene];
+				}
+			}
+		}
+	}
+	
+	if (window == nil) {
+		// Fall back to a standard UIWindow object (won't work with scene-based apps).
+		window = [[self alloc] initWithFrame:[UIScreen mainScreen].bounds];
+	}
+	
+	window.rootViewController = rootViewController;
+	window.windowLevel = UIWindowLevelAlert + 1;
+	
+	return window;
+}
+
+@end
diff --git a/Apptentive/Apptentive/Model/ApptentiveLegacyEvent.m b/Apptentive/Apptentive/Model/ApptentiveLegacyEvent.m
index 53d435562..1cf345ff7 100644
--- a/Apptentive/Apptentive/Model/ApptentiveLegacyEvent.m
+++ b/Apptentive/Apptentive/Model/ApptentiveLegacyEvent.m
@@ -45,7 +45,7 @@ + (void)enqueueUnsentEventsInContext:(NSManagedObjectContext *)context forConver
 
 		// Add custom data, interaction identifier, and extended data
 		if (event.dictionaryData != nil) {
-			NSSet *allowedClasses = [NSSet setWithArray:@[[NSDictionary class], [NSArray class]]];
+			NSSet *allowedClasses = [NSSet setWithArray:@[[NSDictionary class], [NSArray class], [NSString class]]];
 			NSDictionary *dictionaryData = [ApptentiveUnarchiver unarchivedObjectOfClasses:allowedClasses fromData:event.dictionaryData];
 
 			payload.customData = dictionaryData[@"custom_data"];
diff --git a/Apptentive/Apptentive/Model/ApptentiveLegacySurveyResponse.m b/Apptentive/Apptentive/Model/ApptentiveLegacySurveyResponse.m
index 08068732e..9a9b9aac0 100644
--- a/Apptentive/Apptentive/Model/ApptentiveLegacySurveyResponse.m
+++ b/Apptentive/Apptentive/Model/ApptentiveLegacySurveyResponse.m
@@ -81,7 +81,7 @@ - (NSDictionary *)dictionaryForAnswers {
 		return @{};
 	} else {
 		NSDictionary *result = nil;
-		NSSet *allowedClasses = [NSSet setWithArray:@[[NSDictionary class], [NSArray class], [NSString class]]];
+		NSSet *allowedClasses = [NSSet setWithArray:@[[NSDictionary class], [NSArray class], [NSString class], [NSNumber class]]];
 		result = [ApptentiveUnarchiver unarchivedObjectOfClasses:allowedClasses fromData:self.answersData];
 		return result;
 	}
diff --git a/Apptentive/Apptentive/Networking/Requests & Payloads/ApptentiveLegacyConversationRequest.m b/Apptentive/Apptentive/Networking/Requests & Payloads/ApptentiveLegacyConversationRequest.m
index 8a992fc89..371eda697 100644
--- a/Apptentive/Apptentive/Networking/Requests & Payloads/ApptentiveLegacyConversationRequest.m	
+++ b/Apptentive/Apptentive/Networking/Requests & Payloads/ApptentiveLegacyConversationRequest.m	
@@ -34,7 +34,7 @@ - (NSString *)path {
 	return @"conversation/token";
 }
 
-- (NSDictionary *)JSONDictionary {
+- (nullable NSDictionary *)JSONDictionary {
 	return nil;
 }
 
diff --git a/Apptentive/Apptentive/Persistence/ApptentiveBackend.h b/Apptentive/Apptentive/Persistence/ApptentiveBackend.h
index f03af8030..135b5b612 100644
--- a/Apptentive/Apptentive/Persistence/ApptentiveBackend.h
+++ b/Apptentive/Apptentive/Persistence/ApptentiveBackend.h
@@ -40,6 +40,8 @@ extern NSString *const ApptentiveHasSentMessageKey;
  */
 @interface ApptentiveBackend : NSObject <NSFetchedResultsControllerDelegate, ApptentiveConversationManagerDelegate>
 
+@property (class, assign, nonatomic, getter=shouldGatherCarrierInfo) BOOL gatherCarrierInfo;
+
 @property (readonly, strong, nonatomic) ApptentiveConversationManager *conversationManager;
 @property (readonly, strong, nonatomic) ApptentiveAppConfiguration *configuration;
 @property (readonly, strong, nonatomic) ApptentiveDispatchQueue *operationQueue;
diff --git a/Apptentive/Apptentive/Persistence/ApptentiveBackend.m b/Apptentive/Apptentive/Persistence/ApptentiveBackend.m
index 0893bd45b..573a35d98 100644
--- a/Apptentive/Apptentive/Persistence/ApptentiveBackend.m
+++ b/Apptentive/Apptentive/Persistence/ApptentiveBackend.m
@@ -50,6 +50,7 @@
 NSString *const ATInteractionAppEventLabelLaunch = @"launch";
 NSString *const ATInteractionAppEventLabelExit = @"exit";
 
+static BOOL _gatherCarrierInfo;
 
 @interface ApptentiveBackend ()
 
@@ -145,7 +146,7 @@ - (void)updateAndMonitorDeviceValues {
 	[ApptentiveDevice getPermanentDeviceValues];
 
 	__weak ApptentiveBackend *weakSelf = self;
-	if ([CTTelephonyNetworkInfo class]) {
+	if ([CTTelephonyNetworkInfo class] && ApptentiveBackend.shouldGatherCarrierInfo) {
 		_telephonyNetworkInfo = [[CTTelephonyNetworkInfo alloc] init];
 		if (@available(iOS 12.0, *)) {
 			ApptentiveDevice.carrierName = [[_telephonyNetworkInfo.serviceSubscriberCellularProviders.allValues valueForKeyPath:@"carrierName"] componentsJoinedByString:@"|"];
@@ -765,11 +766,13 @@ - (void)conversation:(ApptentiveConversation *)conversation addApptimizeExperime
 
 #pragma mark - Paths
 
-- (NSString *)cacheDirectoryPath {
+- (nullable NSString *)cacheDirectoryPath {
 	NSArray *paths = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES);
-	NSString *path = ([paths count] > 0) ? [paths objectAtIndex:0] : nil;
+    if (paths.count == 0) {
+        return nil;
+    }
 
-	NSString *newPath = [path stringByAppendingPathComponent:@"com.apptentive"];
+	NSString *newPath = [[paths objectAtIndex:0] stringByAppendingPathComponent:@"com.apptentive"];
 	NSFileManager *fm = [NSFileManager defaultManager];
 	NSError *error = nil;
 	BOOL result = [fm createDirectoryAtPath:newPath withIntermediateDirectories:YES attributes:nil error:&error];
@@ -792,6 +795,14 @@ - (ApptentiveMessageManager *)messageManager {
 	return self.conversationManager.messageManager;
 }
 
++ (BOOL)shouldGatherCarrierInfo {
+	return _gatherCarrierInfo;
+}
+
++ (void)setGatherCarrierInfo:(BOOL)gatherCarrierInfo {
+	_gatherCarrierInfo = gatherCarrierInfo;
+}
+
 #pragma mark -
 #pragma mark Apptimize SDK
 
diff --git a/Apptentive/Apptentive/Surveys/View Controllers/ApptentiveSurveyViewModel.h b/Apptentive/Apptentive/Surveys/View Controllers/ApptentiveSurveyViewModel.h
index 905373194..c461616a4 100644
--- a/Apptentive/Apptentive/Surveys/View Controllers/ApptentiveSurveyViewModel.h	
+++ b/Apptentive/Apptentive/Surveys/View Controllers/ApptentiveSurveyViewModel.h	
@@ -39,7 +39,7 @@ NS_ASSUME_NONNULL_BEGIN
 @property (readonly, nonatomic) NSString *thankYouText;
 @property (readonly, nonatomic) NSString *missingRequiredItemText;
 
-@property (readonly, nonatomic) NSIndexPath *firstInvalidAnswerIndexPath;
+@property (readonly, nonatomic, nullable) NSIndexPath *firstInvalidAnswerIndexPath;
 
 - (NSInteger)numberOfQuestionsInSurvey;
 - (NSInteger)numberOfAnswersForQuestionAtIndex:(NSInteger)index;
diff --git a/Apptentive/Apptentive/Surveys/View Controllers/ApptentiveSurveyViewModel.m b/Apptentive/Apptentive/Surveys/View Controllers/ApptentiveSurveyViewModel.m
index 5e9021cf6..f339fbd82 100644
--- a/Apptentive/Apptentive/Surveys/View Controllers/ApptentiveSurveyViewModel.m	
+++ b/Apptentive/Apptentive/Surveys/View Controllers/ApptentiveSurveyViewModel.m	
@@ -455,7 +455,7 @@ - (BOOL)validate:(BOOL)isSubmit {
 	return self.invalidQuestionIndexes.count == 0;
 }
 
-- (NSIndexPath *)firstInvalidAnswerIndexPath {
+- (nullable NSIndexPath *)firstInvalidAnswerIndexPath {
 	__block NSUInteger minIndex = NSNotFound;
 	[self.invalidQuestionIndexes enumerateIndexesUsingBlock:^(NSUInteger idx, BOOL *_Nonnull stop) {
 	  minIndex = MIN(minIndex, idx);
@@ -535,7 +535,7 @@ - (ApptentiveSurveyQuestion *)questionAtIndex:(NSInteger)index {
 	return [self.survey.questions objectAtIndex:index];
 }
 
-- (ApptentiveSurveyAnswer *)answerAtIndexPath:(NSIndexPath *)indexPath {
+- (nullable ApptentiveSurveyAnswer *)answerAtIndexPath:(NSIndexPath *)indexPath {
 	NSArray *answers = [self questionAtIndex:indexPath.section].answers;
 
 	return answers.count > (NSUInteger)indexPath.row ? answers[indexPath.row] : nil;
diff --git a/Apptentive/Apptentive/Surveys/Views/ApptentiveSurveyAnswerCell.m b/Apptentive/Apptentive/Surveys/Views/ApptentiveSurveyAnswerCell.m
index 567767b8a..342bca8ad 100644
--- a/Apptentive/Apptentive/Surveys/Views/ApptentiveSurveyAnswerCell.m
+++ b/Apptentive/Apptentive/Surveys/Views/ApptentiveSurveyAnswerCell.m
@@ -14,7 +14,7 @@
 @implementation ApptentiveSurveyAnswerCell
 
 - (BOOL)isHidden {
-    return super.hidden && !self.forceUnhide;
+	return super.hidden && !self.forceUnhide;
 }
 
 @end
diff --git a/Apptentive/ApptentiveTests/ApptentiveConversationTests.m b/Apptentive/ApptentiveTests/ApptentiveConversationTests.m
index c067516df..f6ccf8a1a 100644
--- a/Apptentive/ApptentiveTests/ApptentiveConversationTests.m
+++ b/Apptentive/ApptentiveTests/ApptentiveConversationTests.m
@@ -11,6 +11,7 @@
 #import "ApptentiveCount.h"
 #import "ApptentiveDevice.h"
 #import "ApptentiveEngagement.h"
+#import "ApptentiveRandom.h"
 #import "ApptentivePerson.h"
 #import "ApptentiveSDK.h"
 #import "ApptentiveVersion.h"
@@ -72,6 +73,8 @@ - (void)testConversation {
 	[self.conversation endSession];
 
 	XCTAssertNil(self.conversation.sessionIdentifier);
+
+	XCTAssertNotNil(self.conversation.random);
 }
 
 - (void)testAppRelease {
@@ -265,6 +268,12 @@ - (void)testEngagement {
 	XCTAssertEqualWithAccuracy(testInteraction.lastInvoked.timeIntervalSince1970, [[NSDate date] timeIntervalSince1970], 0.01);
 }
 
+- (void)testRandom {
+	XCTAssertEqualObjects([self.conversation.random valueForFieldWithPath:@"percent"], @50);
+	XCTAssertEqualObjects([self.conversation.random valueForFieldWithPath:@"xyz/percent"], @50);
+	XCTAssertNil([self.conversation.random valueForFieldWithPath:@"xyz/abc/percent"]);
+}
+
 - (void)testNSCoding {
 	ApptentiveMutableConversation *mutableConversation = [self.conversation mutableCopy];
     
@@ -295,6 +304,8 @@ - (void)testNSCoding {
 
 	[mutableConversation startSession];
 
+	[mutableConversation valueForFieldWithPath:@"random/xyz/percent"];
+
 	NSString *path = [NSTemporaryDirectory() stringByAppendingString:@"conversation.archive"];
 
 	[ApptentiveArchiver archiveRootObject:mutableConversation toFile:path];
@@ -334,6 +345,9 @@ - (void)testNSCoding {
 	XCTAssertEqual(testInteraction.versionCount, 0);
 	XCTAssertEqualWithAccuracy(testInteraction.lastInvoked.timeIntervalSince1970, [engagementTime timeIntervalSince1970], 0.01);
 
+	NSMutableDictionary *randomValues = [conversation.random valueForKey:@"randomValues"];
+	XCTAssertEqualObjects(randomValues[@"xyz"], @0.5);
+
 	XCTAssertNil(conversation.sessionIdentifier);
 }
 
diff --git a/Apptentive/ApptentiveTests/Info.plist b/Apptentive/ApptentiveTests/Info.plist
index 243b4b37d..973ce43e0 100644
--- a/Apptentive/ApptentiveTests/Info.plist
+++ b/Apptentive/ApptentiveTests/Info.plist
@@ -15,7 +15,7 @@
 	<key>CFBundlePackageType</key>
 	<string>BNDL</string>
 	<key>CFBundleShortVersionString</key>
-	<string>5.3.3</string>
+	<string>5.3.4</string>
 	<key>CFBundleVersion</key>
 	<string>1</string>
 </dict>
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0eb8632dc..cd295f46c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,14 @@
+# 2021-08-02 - v5.3.4
+
+#### Improvements
+
+* Add a flag to disable CoreTelephony framework import
+
+#### Bugs Fixed
+
+* Fix window-based interaction presentation for `UIScene`-based apps
+* Fix unarchiving warnings for iOS 15
+
 # 2021-06-16 - v5.3.3
 
 #### Bugs Fixed
diff --git a/Example/Podfile.lock b/Example/Podfile.lock
index 161c01dcb..02e46b256 100644
--- a/Example/Podfile.lock
+++ b/Example/Podfile.lock
@@ -1,5 +1,5 @@
 PODS:
-  - apptentive-ios (5.3.3)
+  - apptentive-ios (5.3.4)
 
 DEPENDENCIES:
   - apptentive-ios (from `..`)
@@ -9,8 +9,8 @@ EXTERNAL SOURCES:
     :path: ".."
 
 SPEC CHECKSUMS:
-  apptentive-ios: 90329e56e39cc4df71e67f6dd8eadc899cd8aba1
+  apptentive-ios: e5be8ad11cfad2259a0063150ce898b04b7c1090
 
 PODFILE CHECKSUM: 785a9d76c0ca2535819b754c6fe8c5c6413dbc30
 
-COCOAPODS: 1.8.4
+COCOAPODS: 1.10.1
diff --git a/apptentive-ios.podspec b/apptentive-ios.podspec
index 9841b4fe8..0d2fe00ce 100644
--- a/apptentive-ios.podspec
+++ b/apptentive-ios.podspec
@@ -1,7 +1,7 @@
 Pod::Spec.new do |s|
   s.name     = 'apptentive-ios'
   s.module_name = 'Apptentive'
-  s.version  = '5.3.3'
+  s.version  = '5.3.4'
   s.license  = 'BSD'
   s.summary  = 'Apptentive Customer Communications SDK.'
   s.homepage = 'https://www.apptentive.com/'