Existing phone fingerprint readers are less than ideal. When they're on the back, you can't sign in while the phone sits on your desk; on the front, they chew up valuable device real estate; on the side, they're tiny. That's where LG Innotek might just come to the rescue. It developed a fingerprint sensor that hides just under the cover glass on a mobile device, saving space while giving your digits an easy target. On top of that, it can actually be more effective than a dedicated button. It's extremely accurate (the failure rate is just 0.002 percent), and the stealthy approach protects the reader against scratches and water.