John Gruber and Dan Benjamin briefly speculated on what a gesture sensitive button could be used for in iOS on the most recent episode of The Talk Show. Would it behave like the nub ball on Blackberries, used for scrolling? Likely not. What about the Palm Pre, where the gesture area can be used as a back button, with a right-to-left swipe? Again, probably not. I believe that if this new gesture region is in fact coming to the iPhone, it will be used for only one thing: switching between open apps.
Iâ€™m not one for making predictions, but if this new home button rumor turns out to be real, I hope Dan (Provost) is right. The reason the iPhone is such a popular device is because directly manipulating objects on the screen provides an incredibly compelling user experience. Trying to delegate any of those direct interactions to an off screen hardware element just doesnâ€™t make sense to me.