December 12, 2012, 4:35 PM — Here's how you can turn on the Liveness Check for additional security on your Android device. This will require you to blink when using face unlock.
1. Go to the Screen Security settings menu.
2. Tap the Liveness Check option.
For more, see the original article at the link below.
50 Android Jelly Bean tips, tricks and hints | Tech Radar