Flashing black quads and triangles started appearing when starting one of the tutorials. Went away after minimizing the game and going back to it.
Hi @koomz0r and thank you for reporting this! Can you remember which level it was? And let us know if it happens again!
Happens everywhere, menus and levels just the same. Most of the time one can get rid of it by putting the game on the background, sometimes not. Looks suspiciously like a sync problem with page flipping, could be a cock up in the graphics driver of Xperia.