Me too!
I also get this behavior on Samsung Galaxy S3, at least versions 0.5.0 - 0.6.1.
It is easy to reproduce: play some time,then power-off / power-on or switch to another app.
Start again MCPE, turn left or right about 180 degrees, and the screen flicker appears.
It also appears when the S3 goes itself in sleep power mode.
It happens sometimes for no apparent reason, maybe when some other app awakes, not sure about this.
Sometimes it disappears when looking upwards or downwards then reappears when looking in some precise direction.
Workaround: kill app (press home button, task manager, force exit), start again MCPE, load world, ok able to play on.
Minecraft Demo (v0.2.1) doesn't show the behavior.
Could it be related with the Quad-core of the GS3 ?
Maybe related, please look at MCPE-1072 - "Screen Flicker's All The Time" ;
I must check if the flicker also appears after 6 minutes like your freeze.
With Android 4.2.1 / Cyanogenmod 10.0