The dominant control interface for any device has to be incredibly robust. It has to be useable in almost every conceivable situation, and for almost every conceivable purpose the device is intended to be used for. The edge cases it doesn't cover have to be covered by an even more robust, but perhaps less sophisticated alternate.<p>Keyboard and mouse allow very rapid and precise text input, rich option and function choice, and very precise selection and movement control. Touch pads do a very good job or replacing the mouse for mobile devices like laptops.<p>For a long time touch wasn't up to scratch. Pens allowed more precise selection and motion, but were always a kludge because the pens themselves were too easy to misplace or drop while on the go. Once touch's early imprecision was overcome, it took over because you always have your fingers with you. Note that there is one case where touch isn't enough - controlling volume settings for your phone while in your pocket. In this edge case, physical buttons take up the slack. My point is not that touch has limitations (it does), but that you need to take a very long, hard look at any technology intending to replace it to be sure it is even more robust, and even more convenient and precise and has even fewer limitations in a huge range of situations.<p>Motion controllers like TouchMotion are extremely limited compared to touch. You can't use it in a relaxed posture, you have to have your hands raised and posed in the space that will accept gesture input. For precise selection, you need to have a cursor on screen like a mouse, because you don't have the directness of touch. Also while it's not ideal to use touch on a train or bus that's moving, trying to use something like TouchMotion would be a joke.<p>Voice control is highly problematic too. People actually find it extremely hard to be precise, to the level that many interactions with computers require, in verbal communication. That goes double for describing visual or spacial information verbally. Anyone that's ever worked phone tech support for computer users knows what I'm talking about.<p>Eye tracking has possibilities, but our eyes wander around and shift focus point all the time. Sometimes we want to look at something other than the thing we're controlling. Also I suspect that maintaining the disciplined and precise eye movements you'd need to replace touch or mouse/trackpad would be pretty onerous.<p>So I don't see touch going away for a very long time, if ever. I remember in the 90s pundits predicting that keyboards and mice were just placeholders and they'd be gone within a few years. The truth is you'd better get used to them because they're here to stay, and so is touch.