World’s Smallest Device to Prevent Skin Cancer, Mood Disorder Risk

Users can glue the device on to their hats, clip it to sunglasses or stick it on their nail.

Scientists have developed the world's smallest wearable, battery-free device that can warn people of overexposure to ultraviolet rays (UV) - a leading factor for developing skin cancer.

Currently, people do not know how much UV light they are actually getting. The rugged and waterproof device interacts wirelessly with the phone and helps maintain an awareness and for skin cancer survivors.