Smartphones today compete over which can best secure your secrets. They encrypt your data, store the digital keys to unlock themselves on specialized hardware, and even offer fancy biometrics from fingerprints to faceprints. But many millions of smartphones remain open to an absurdly low-tech attack: a sly glance at someone's phone while they unlock it. One new study has quantified just how easy an Android-style unlock pattern--as opposed to a six-digit PIN or biometric unlock--makes the job of any over-the-shoulder snoop. Security researchers at the US Naval Academy and the University of Maryland this week published a study that shows that a casual observer can visually pick up and then reproduce an Android unlock pattern with relative ease. In their tests, they found that six-point Android unlock patterns can be recreated by about two out of three observers who see it performed from five or six feet away after a single viewing.