The research skunkworks of Google, Google X, is investigating combining nanoparticles introduced to the bloodstream via a pill, with a wrist-worn sensor that would detect where the nanoparticles attach. They could attach to cancer cells, fatty plaques in blood vessels, or analyze the chemical composition of blood to detect imbalances. The wrist-worn sensor (which looks awfully like a smartwatch) would upload the readings of the nanoparticles via light and radio waves one or more times a day. By going public at this stage, the intent of Google X is to license out the technology for further development and to find partners. The BBC News Technology article has an unfortunate headline not backed up in the article: Google is developing cancer and heart attack detector