Leap Motion: hand and finger motion controller

I agree tactile feedback would be helpful. But it's not as critical here as it would be on a normal touch screen. Here you at least have visual feedback. Because on a touchscreen you only have two states: touch and not touch. Your app cannot know where the user finger is when he's not touching, that's why there are no cursors and onFocus elements lose their meaning.

But if the leap is as good as in the videos, then your app could show a cursor of where the fingers are before touching the UI. And you can use that as a visual feedback to the user to help him mentally locate himself. So I'd guess using a virtual keyboard on the leap would be much more efficient to work on than a touchscreen virtual keyboard.

Of course, since the existing apps won't be expecting this, it will be hard to use existing stuff. Ideally, people will have to adapt their apps to this input instead of trying to just migrate from touch.