Not sure if it's my phone, but this game is very glitchy - every few pieces an ad interrupts the game freezes, losing progress on the puzzle. Still enjoyable, but have to play in airplane mode to avoid this issue The other problem is "missing" pieces- this last one I lost 4 pieces. The rest of the puzzle is done and they are nowhere. Previously I found pieces hiding off screen and could pull them in, but not this time. At one hint per piece, it's not worth it to finish the puzzle.