Android smartphone son took viber read messages or just watch phone and faced with the protection in the form of photo-password? When unlocking the tablet is done with the face of the owner, ie a comparison of images of that at the moment, and that was done at the time of installation protection.

This technique of protection is not reliable and it can break off, it is even easier than off Pattern Lock.

How do I delete a photo-password on Android

Algorithm off photo-password is very easy one, the photo you need to find the person ovnera tablet or video close-up and bring it to the tablet, TV or monitor, then you can unlock Android tablet by moving the front camera on the output image. 

Thus the image of a man gives you a 100% for Kent. Even the Android to the report, that the principle of protection is not very Burglar any person similar to you may realize unlock your device.