What if your cell phone could detect cancer cells circulating in your blood or warn you of an imminent heart attack? Mobile wireless digital devices, including smartphones and tablets with seemingly limitless functionality, have brought about radical changes in our lives, providing hyper-connectivity to social networks and cloud computing. But the digital world has hardly pierced the medical cocoon. Until now. Beyond reading email and surfing the Web, we will soon be checking our vital signs on our phone. We can already continuously monitor our heart rhythm, blood glucose levels, and brain waves while we sleep. Miniature ultrasound imaging devices are replacing the icon of medicine—the stethoscope. DNA sequencing, Facebook, and the Watson supercomputer have already saved lives.