BlueSudoku: Calm Puzzle

BlueLogic Sudoku — a clean, minimal Sudoku puzzle experience. • 5 difficulty levels: Easy, Medium, Hard, Expert, Evil • Unique solution guarantee for every puzzle • 9 handcrafted color palettes — Amber, Paper, Sakura and more, with gradient previews • Light & dark mode, including an AMOLED true-black theme • Note mode (pencil marks) + smart auto-note cleanup • Error highlighting (optional) — wrong cells get a clear cross mark • Hints with undo — free daily quota, watch a short ad for extra • Sound effects and dedicated game haptics (each can be toggled off) • Statistics per difficulty + daily streak • Game Center achievements • Offline-first — no account needed

No interstitials. No pop-ups. Just one discreet banner at the bottom that you can remove with a single in-app purchase.