This app makes some interesting design choices in the way it presents sudoku puzzles. I don’t see how the completed puzzle relates to the pixelated image you can sometimes earn upon solving the puzzle. The biggest negative I see of this particular app, is the fact that there’s a setting that allows you to turn off h automatic hints for potential moves. I have yet to turn this setting on, and it still gives you hints. All you need to do is highlight any empty space and it will make the remaining values in the 3x3 square in which you highlighted the space, stand out. Furthermore, the app calls you out if you make a mistake. If these aren’t hints, I don’t know what a hint is. It’s quite annoying actually.
Furthermore, the daily challenges border on the ridiculous. Over and above ones like “place a 6 then an 8 two times" you’ll occasionally get a challenge that says something like "complete three columns back to back" whose definition of "back to back" is questionable at best. I got this challenge and played two puzzles by literally completing all nine columns left to right, and the meter never once went beyond a streak of 1. I simply can’t recommend this app to anyone over, say, the age of 8 when there are so many better sudoku apps out there.
If you want a truly great sudoku app, look to the (non-Apple Arcade) one created by Conceptis Ltd.