Ocassionly, when the screen is locked, strange pictures would appear on screen along with the following text near the bottom of the phone (writing from memory, so might not be exact) "Double tap a sample photo to exit the demo mode..."
What is it? And how can it be disabled? I couldn't find anything in setting.
P.S. I've enabled Developer Options. There is a setting called "Demo Mode", but it's switched off.
Other than that, found a pre-installed app "Retail Demo". But it cannot be unistalled.
