Will do on tuesday since that is my next work day. Also did you use the screen position node in materials while developing for mobile? Just to go sure.
Maybe i can describe it a bit better untill then: I get the screen position of the character and do a sphere mask there. The spehre mask gets fed in the character position and the output of the ScreenPosition node to cut out a hole in a screenwide material(anchored to all edges of the screen in a widget). If the character is at 500,100(screen coordinates x,y) the hole appears at 500, screen hight - 100(in ladscape mode, dont know if anyhting else is affected). And as i move the character upwards the hole moves down.
Works normal on the preview on pc and on the Xperia One, but the Xperia 3 Compact and the Libero S10 have that bug.
Hope this helps to clarify the problem. And thanks for the help.