Tap pressure strength detection using accelerometer

Question

Yesterday, in the presentation about the new Garageband for iPad 2, Apple demoed an interesting feature: The detection of the tap pressure by using the accelerometer. (See t

Answer 1

Even if the SDK exposes to us the touch area only, I believe the screen hardware is providing to the operating system much more info: touched pixels (used for area detection) and touch duration. Together (and experimenting) they can give you a good estimate of the applied pressure. It would be nice if Apple were releasing this empirical pressure estimation to developers.