There's a fingerprint scanner in the iPhone 5S, and it's hiding under the home button. While iOS provides a numeric entry gate in front of each iPhone, Apple' says only about half the people bother using it. So, the iPhone 5S implements Touch ID, a fingerprint sensor below the home key that's activated by a stainless steel detection ring surrounding the button. Inside is a thin capacitive sensor that scans at 500 pixels per inch to recognize the signature print regardless of orientation. The sensor is covered by a sapphire crystal that's impervious to scratches, and according to Apple, prints are encrypted, stored locally and never uploaded or accessible by other apps. Android provides screen-lock security through a pattern that's dragged in a grid, numerical PIN or password. For Galaxy S4, Samsung adds facial recognition and KNOX, a kernel-level security solution with boot protection.