Fiddling with small buttons or touchscreens on your mobile device when you're running, riding a bike or even just crossing the street can be a frustrating – and dangerous – endeavor. NEC is looking to solve this dilemma by developing a system that enables users to operate devices by just tapping their arm. The ArmKeypad is made up of acceleration sensors worn on each wrist that determine the area of the arm tapped by a user and translate this into different input commands via a Bluetooth link.

Announced by NEC in March and spied at Interaction 2011 by DigInfo TV, the system can detect whether the arm has been tapped by the left or right hand or if the user has clapped their hands. It can measure the strength of the tapping vibration and the tap's location on the arm.

One of the obvious applications is to control music while running allowing the user to stop and start the music, adjust the volume and select tracks.

Simpler and easier to learn that a gesture control systems, NEC says the commands are "easy to remember and are nearly free from input errors."

The company intends to refine the technology to about the size of a watch or wristband and a commercial version is expected in one or two years.

If tapping isn't your thing, you might have to hold out for systems that turn your arm itself into a touchscreen to reach maturity.