Google has filed a patent suggesting users stick out their tongue or wrinkle their nose in place of a password.
It says requiring specific gestures could prevent the existing Face Unlock facility being fooled by photos.
The Jelly Bean version of Android introduced the need for users to blink their eyes as a check, but users soon demonstrated it could be fooled.
A spokesman for Google was unable to comment on when the suggested technology might be implemented.
|The patent suggests users would have to type in a password if they failed to make the right gestures|