A smart contact lens that can monitor the glucose levels of diabetes sufferers was developed by Google in January

Google smart contact lens
The smart contact lens contains chips and sensors "the size of glitter" to monitor blood sugar levels
Coming out of the company's Google X skunk works division, best known for developing Google Glass, the contact lenses use chips and sensors the size of glitter to offer an early warning to the wearer by analysing tears.
"As you can imagine, tears are hard to collect and study," the Google engineers said. "At Google X, we wondered if miniaturised electronics - think: chips and sensors so small they look like bits of glitter, and an antenna thinner than a human hair - might be a way to crack the mystery of tear glucose and measure it with greater accuracy."