Extreme Difficult Sudoku 2500

The controls are slightly unintuitive. It took a while for me to realize that the "pin" button holds down the number I want, thus allowing me to fill in squares without constantly returning to the number selection. Despite this singular issue i have with the app, there are an incredible amount of puzzles and difficulties without really other drawbacks. Ads aren't too bad imo, and easy to avoid. By far one of my favorite apps.

It'd be an improvement to have a note automatically deleted once we fill the corresponding digit in a square. I.e. if I have 1 in notes across the board and I set a regular 1 in a square, all 1 notes should automatically disappear. Also, checking for mistakes should be feasible at any time during the game, not only once all squares have been filled out. And last, we should have a button to show the mistakes so that we can correct them during the game.

Good app with uncloseable ads. I enjoy the puzzles and the interface is nice and simple. But the fact that I can't close the ads is so annoying, I have to play the ads (they are the playable ones) then let it take me to Play Store to close the ad. I'm totally ok with the ads that you have to watch them for 15-30 secs before you can close it [emphasis on CLOSE]. If you are ok with uncloseable ads, go for it, this is a good app but I can't take it.