A device known as iSkin has been developed at Max Planck Institute for Informatics and Saarland University. There are numerous versions of this device, each with a different shape and size, all of which include pressure sensors to allow the user to control their mobile devices using their body.

Scientists in Germany have developed a sensor that can be worn on the skin to turn it into a surface for controlling mobile devices such as smartphones and smartwatches ~ Catchy Net