Developer Owen Goss has made some really interesting puzzle games for iPhone and iPad, including the excellent LandFormer. He also built an app called Baby's Musical Hands that emphasizes simple interaction with the iPad. Clearly, he's very interested in the iPad's tactile possibilities. His latest game, Finger Tied, explores the idea even further by asking players to directly interact with the glass screen in several ways.
The core idea is simple. There are a few different shapes on the screens with tracks attached to them. Your goal is to drag your fingers across the screen and follow those different tracks. As you can see above (and in our video below), this can get difficult as the levels go up, sometimes requiring you to independently operate up to four different fingers at once.
The game also has a very nice and intuitive level creation editor, where you can make your own levels in a snap. Unfortunately, I can't find an easy way to share custom levels, so maybe that's a feature that will be in the pipeline for a later date.
At any rate, Finger Tied is an excellently designed title, and demonstrates how much thought Goss has put into the touchscreen's potential. The game's currently available at a launch sale price of just US$0.99, making it a must-buy for anyone with 10 fingers and an iPad.