Nine: Sudoku

Nine is sudoku built for wherever you are...on the couch, the train, the desk, or the wrist. One purchase for iPhone, iPad, Mac and Apple Watch, and your boards follow you between them.

FLICK TO PLAY Tap a cell and a ring of nine digits blooms around it. Flick toward the one you want. On the Mac it's the arrow keys and the number keys; on Apple Watch it's the Digital Crown.

PUZZLES YOU CAN TRUST Every board has exactly one solution and is checked by a logic solver before you see it, so you never need to guess. Three difficulty bands set which techniques a puzzle may ask for... from a relaxed first coffee to a proper fight.

CLASSIC, THERMO AND KILLER Turn the page from classic sudoku to Thermo, where digits climb along each thermometer, and Killer, where cages add up to their sums.

A COACH THAT EXPLAINS Stuck? Ask why a cell must be a seven and Nine walks you through the reasoning instead of just filling it in. The Technique School teaches each method on boards built to show it.

YOUR SOLVE, REPLAYED Finish a board and watch it play back as a comet across the grid, with a debrief of where you flew and where you slowed down. Your history keeps every solve.

MADE FOR EVERY SCREEN • iPhone and iPad: touch-first, with Apple Pencil handwriting and a drafting table on iPad. • Mac: keyboard-native, with a menu bar, a History window and a compact always-on-top desk mode. • Apple Watch: zoom into one box at a time and dial digits with the Crown. • Home Screen widget with a board you can play.

QUIET BY DESIGN No ads. No in-app purchases. No account. No tracking. Nothing blinks at you while you think. Dark-first, with light mode on iPhone, iPad and Mac.

Game Center leaderboards and achievements, iCloud sync across your devices, and full support for VoiceOver and Dynamic Type. Available in English, German, Spanish, French, Italian, Japanese, Korean, Dutch, Brazilian Portuguese and Simplified Chinese.

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