Halloween Artist is a jack-o-lantern simulation toy. It is a web app,
available for use on computers, tablets, phones, etc at:
http://halloweenartist.penduin.net
A live demo is also available here on GitHub:
http://penduin.github.io/halloweenartist
Halloween Artist on the Firefox Marketplace:
https://marketplace.firefox.com/app/halloween-artist
I've done a write-up about how I put this together:
http://penduin.blogspot.com/2013/10/halloween-artist-revisited-in-geeky.html
The original TouchPad app:
https://developer.palm.com/appredirect/?packageid=net.penduin.halloweenartist