Samsung is rumored to have developed a "floating touch" feature on the Galaxy S4 that will allow users to navigate their phones without ever touching the display.
The feature would be especially helpful in situations where it would be easier to wave your hand or finger above your screen than actually touch it. Samsung is reportedly using Atmel's newest maXTouch S controllers, which could allow you to quickly answer a call, see the contents of a photo gallery before you open it and scroll without ever touching the screen.
Samsung has already premiered touchless navigation via the S-Pen in the Galaxy Note 2, so they no doubt have the capacity to pull this off. But with the Galaxy S4, we assume there would be no stylus involved.
Pantech Vita also features gesture control but it does so using the front-facing camera, which consumes a lot of battery life in a very short period of time. Samsung's solution is rumored to be much more battery efficient.
Of course, this is all just a rumor at this point. But compared to the rumors about a flexible display, this one is far more likely to end up being true.