One thing I don’t like about touch screens is the lack of feel of touch of a button, You dont accidently hit anyother key while using physical keys, and you donot have to physically see the keys while typing on physical keys. I still use a qwerty for exactly that reason. But I’m not the only one that feels the same, and that is why various companies are deisnging touch screens that grows 3D buttons and knobs where and when you want them; And they controls would recede into the touch screen surface after they’ve served their purpose.
The technique behind the design calls for sandwiching a fluid between touch-screen layers and pushing the fluid around with a series of tiny valves. The top layer is flexible, so pushing the fluid to one part of the screen raises the surface there. There are two companies known right now that are experimenting with this tech. Tactus Technologies is working on this tech with a fluid in between while CMU (Carnegie Mellon University) morphing touch screen uses air to do it. Check the tech out yourself in video below: