It's a engaging game, the idea that every piece is randomized is fun and difficult. I only rate three stars becuase the game keeps randomly crashing when I play on Freeplay. It started happening when I was playing on rank 17 and did not happen on lower ranks. I cleared my cashed data and that didn't work. I still enjoy the game but it's slightly annoying that it crashes randomly. Edit: It may be crashing because my phone is about 4-5 years old.