Face Unlock becomes smarter in Jelly Bean: asks you to blink for the camera
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Face Unlock was one of the coolest new features in Android 4.0 Ice Cream Sandwich, but while having your phone recognize your face sounds like a fun (it is) way to access your device, it definitely isn’t among the most secure ones.

Is it still possible to trick Face Unlock, though? Certainly. All it takes is a bit of tech savvy to craft an animation out of still photos with you with open and closed eyes, and then play it to your phone’s camera from another display. But still, that’s much harder than just showing a picture, isn’t it?
Anyway, we’d only use Face Unlock for the fun and coolness of it, not for real safety, and we’d advise you to do the same.
source: Droid-life

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