Super-thin electronic skin lights up a digital display on your hand

Imagine having a fitness tracker that doubles as a temporary tattoo. Or a monitoring device that doctors can paste straight onto an ailing organ. Or a watch so unobtrusive that it looks like it's built right into your wrist. These are all long-term possibilities for electronic skin (or e-skin) — ultra-thin and ultra-stretchy material that can mimic the flexibility of human skin. New e-skin research is happening all the time, but today, researchers at the University of Tokyo are introducing a new method of turning it into an electronic display.