The only thing saving you from receiving 1 star is the fact that the game is good and playable. There are loads of ads, and that bothers me. I know you have to get paid, but you really don't need a pop-up ad every time you change screens (I wish I was exaggerating) and ads at the bottom. I encountered one which was unskippable unless I completely closed the app and restarted it. It's fine and the sudoku part is worderful, but I bet I've watched around 60+ ads in the 2 days I've had this game.