There have been plenty of security holes involving mobile device lock screens, but a recently discovered Android flaw may give you more reasons than usual to be cautious. The technique bypasses the lock screen on most versions ofAndroid Lollipop by crashing it with any large-enough password -- all you need to do is work with that text while the camera app is open, and then enter it into the password prompt. When the attack works, you have as much access as the hardware's rightful owner.

http://www.engadget.com/2015/09/16/a...n-bypass-flaw/