Square One: Daily Sudoku

Square One brings daily Sudoku, guided solving, and fresh puzzles into a calm, focused space. Play solo offline, or share a puzzle link when you want to challenge a friend.

LEARN AS YOU SOLVE
A short illustrated guide introduces the rules. During a puzzle, Learn explains a logical next step on your board. Practise Naked Singles, Hidden Singles, Naked Pairs, and Box-Line reductions at your own pace.

A PUZZLE FOR EVERY DAY
Solve the daily board, build a streak, and review your completed daily puzzle. Choose Easy, Medium, Hard, or Expert for a new board whenever you like. Every generated puzzle has one solution. Daily Deduction offers a short, one-move logic challenge with an explanation of the reasoning.

MAKE IT YOURS
Use pencil notes, smart highlighting, zoom, undo, and hints. Track solve times, scores, achievements, and technique progress. Earn coins by completing distinct puzzles, then use them to unlock color themes and alternate app icons. Preview a theme before choosing it.

CHALLENGE A FRIEND
Share a puzzle link or QR code so someone else can try the same board and beat your time. On Android devices with Google Play services, host or join a nearby puzzle race. Compare a short code on both phones, solve the same puzzle, and choose whether to share live race progress.

YOUR PACE, YOUR SPACE
Solo puzzles work offline. Square One has no ads and no account system of its own. Puzzles and settings are stored on your device. If you sign in to supported platform game services, some progress and achievements may sync across devices. Optional reminders are scheduled on your device.

Recent changes:
Square One has a refreshed home screen and improved tablet layouts, with better use of larger screens in portrait and landscape. Try Daily Deduction, a daily one-move logic challenge. Share puzzles by link or QR code, or race nearby Android friends on the same board. Earn coins through puzzles, streaks, and achievements to unlock themes and alternate app icons.