Microsoft recently showed off their LucidTouch concept technology that lets you control a mobile device via touchscreens on the front and back.
Although currently just a concept (the proof-of-concept device shown has a clunky camera sticking out from the back to monitor the user’s fingers), Microsoft hopes to eventually implement the technology in a small portable gadget.
LucidTouch allows the user to control a gadget via a touchscreen without obscuring the screen at all. When positioned behind the device, the user’s fingers are projected onto the screen, giving it a semi-transparent effect. It’s almost as if you can see through the screen, but the only thing you see is your fingers. A touch-sensitive surface on the back acts much like a regular touchscreen, allowing a person to “click” from the other side of the device.
We can imagine quite a bit of applications for LucidTouch (for example, scrolling around a map as shown in the picture), but it will probably be a while before this technology will become affordable to the consumer.