FlashBuilder 4.6 has some nice functionality for quickly building a UI that work on a desktop or mobile device. You could use FluorineFX (free) or webOrb on a webserver to send data back and forth to a database server if that were needed. If you build it with the Flashbuilder 4.6 mobile project template, it would work on a iPad, mac, windows pc, or android device as well. Since a pc touchscreen should use the same type of finger gestures as a mobile app, this might be a nice way to go. (I don't actually have a touchscreen on my pc, but it runs well with a mouse, so I'd assume it worked with gestures too).
Adobe.tv has lots of examples of building a mobile app project (Which also runs on a PC) and there is a Flashbuilder 4.6 free trial.
http://flex.org/