Double-side Multi-touch Input for Mobile Devices

Rather then having only a single screen for input why not have two? With two screen you are able to do interacted with objects on the screen in a more realistic fashion. By adding a touch screen to the back side of a mobile device you can grab, drag, and manipulate objects as if you were holding them in the real world, and potentially increases the number of functions the user can preform.

Another advantage of using two touch screens rather then one is for simple space saving issues. By being able to preform actions like scrolling and zooming with the back touch screen the user has more space to view and interact with object on the front screen. 

Even though there is only a prototype of this two touch screen device, there have been several studies showing it is not more complicated and confusing for the user having two touch screens instead of one. 

By creating a device which has additional functionally built right into it with a second touch screen and it doesn't come at the cost of added confusion for the user but rather may be more intuitive in some cases, it may be the future of mobile devices.