Wearable UV sensor

Fast Company (New York, June 20) -- If you purchase La Roche-Posay sunscreen this summer, it may come with a complimentary device that looks something like a heart-shaped Band-Aid. But it contains miniature electronics that connect to your smartphone and monitor your sun exposure in real time. None of this was possible until 2006, when John Rogers, the head of the Rogers Research Group at Illinois, published a paper with three of his colleagues explaining how they had developed a stretchable form of silicon by cutting and patterning the material into waves, allowing it to expand or compress like an accordion. Also: Lucire (June 20), Appcessories (blog, June 6).