Clean Sudoku：数独游戏与解题

New Features: Daily Challenges with Streaks, Next Step Hints, Leaderboards, Game Center, and support for 14 languages.

Clean Sudoku is a refreshing classic number puzzle: no ads, no subscriptions, just you and the grid. Four difficulty levels with 8,000 puzzles, plus new daily challenges every day; you can also point your camera at a newspaper sudoku to start playing or view answers in seconds.

Daily Challenges
• A new puzzle every day, with calendar tracking of completion days
• Optional evening reminders to help maintain your streak

Scan Any Sudoku
• Snap a photo of a book or newspaper sudoku, or select from your album
• Correct misidentified digits, then start playing or view answers

Learn While Playing
• Hints don’t just fill in one number; they explain the reasoning behind the next move
• Notes, auto-notes, and error/conflict highlighting

Track Your Progress
• Fastest times per difficulty level and Game Center leaderboards
• Best and average time statistics, plus 12 achievements

Play Your Way
• Start with Easy and Medium difficulties, unlocking Hard and Extreme as you improve
• Generate infinite new puzzles, or create your own and share them via code
• Light, soft, and dark themes, plus colorblind-friendly board layouts
• Timer, sound effects, and three-strike limit are toggleable, with one second chance per game
• Offline play supported, with automatic progress saving
• Supports 14 languages

How to Play: Fill the 9×9 grid so that each row, column, and 3×3 box contains exactly one instance of numbers 1 through 9.