HATTIP TO ALEXIS ALLEN of Designing FileMaker for finding this video on touchscreen design:
Always wanted to know the difference between touch-enabled and touch-optimized? Luke W reveals all and how to make your app more touchable.
It’s a bit Microsoft intensive, but contains some good advice. For iPad’s and iPhones, as well as more information on designing on touch devices, check out the iOS Human Interface Guidelines from Apple.