Good, but could be great
Every time you “rank up”, a pop-up interrupts your flow in the game and you have to tap to get 2 measly coins and then go back to playing. It is extremely annoying. The rank up should happen *after* the level is completed. I’m sure most players don’t even care about ranking up, only beating the level.
On levels where more tiles are added as you play, more TIME should be added as well. If it’s a level that (seemingly) never ends, the time limit should reflect that. You end up having to watch 3, 4, or more ads to get enough time to finish on those levels. The most recent one I played like that (level 203) had less than 2 minutes on the timer and added more tiles SIX times! Get real, developers.
Final suggestion - rewards on chests need to include the special items more and coins less. At least make it 50/50. I have thousands of coins, but no special items all the time. I know I can spend the coins on the special items, but getting them in the chests is better.