A future iPhone could be controlled without you even touching it. Apple is exploring touchless gesture control and curved screens, according to the latest rumors from Bloomberg. A display that "gradually" curves inward from top to bottom is still at least two to three years away, while the touch-free tech "likely won't be ready for consumers for at least two years." That's assuming Apple finds merit in continuing with the R&D cycle for it.
Samsung and Motorola have both used touchless gestures in their handsets before, but it sounds like Apple's version is a bit different in terms of implementation. Rather than using motion sensors in the bezel, Bloomberg says that the display itself will apparently act as the sensor and your hands will have to be much closer to the screen as a result.
Of course, Apple works on far out technology all the time, and more often than not, it doesn't come to market. Remember when the company teased swappable camera lenses back in 2012? Or a solar powered iPhone? Well, it's six and eight years, respectively, since those patents were filed and neither feature has been added yet.