A patent that Samsung have submitted for approval for a dual touch-sensor device where both the front and back screens are touch sensitive.
Samsung’s attempt to differentiate from these existing implementations appears to involve the interplay of software with the dual-touch hardware.
So rather than replicating a front-touch, using the rear touch-sensor could trigger a different function using the same on-screen controls.
But don’t get to excited just yet as Samsung are well know for patent applications and file more patent applications every weeks than Nokia, Motorola, RIM and Sony combined. So the patent may never make it to a device.