Other primates have opposable thumbs, sure, but only we have an app for them. It comes with this new prosthetic hand, unveiled last week by developer Touch Bionics.
The powered thumb is controlled by signals from the user's arm muscles or - in a first for upper limb prostheses - via a smartphone app: a tap of the screen and the hand automatically arranges itself into a preset grip. The thumb can move into 24 different positions and new, extra-sensitive fingertip electrodes also give improved dexterity.
"Powered thumb rotation, combined with the mobile app and quick access to all these new grips, gives me natural hand function that I never imagined would be possible," says Bertolt Meyer, who wears one of the new hands.
The app makes it easy to configure presets by group, such as "work", which includes positions ready for typing, handling documents or using a mouse. The app also includes diagnostic tools and training modes for new users.
Games of rock, paper, scissors may never be the same again.