Put a dot on some colours to distinguish them
My eyesight is poor and it is hard to tell the difference when the game progresses. But most importantly, give levels! Easy. Medium. Difficult. Hard. Expert. The games start off boringly easy. Eventually they get to a level I’m comfortable with. Then it’s all too hard. Sudoku lets you pick your level. This would be improved if you could here too. People read these reviews you know!