They could, but I'm not convinced that a touchscreen makes nearly as good a games controller as the old sticks-and-buttons. Controlling something on a flat scr

They could, but I'm not convinced that a touchscreen makes nearly as good a games controller as the old sticks-and-buttons. Controlling something on a flat screen while looking at a different screen puts limits on the number of "buttons" you can have and be able to push reliably. Also, holding an iPhone like a games controller would be uncomfortable over longish periods of time.