Sudoku by Mastersoft

Sudoku ~ Classic Puzzle Games delivers a feature-rich Sudoku experience with six levels—from Simple to the handcrafted 'Sudoku Master'. Enter a newspaper puzzle or create your own, then solve or play with helpful hints. Use notes and color-coding to track candidates, highlight mistakes, and auto-fill possibilities. Each puzzle has a unique solution, and daily play helps you track progress.

Beyond core gameplay, the extension offers puzzle transfer, solve analysis, and advanced techniques like Swordfish, X-Wings, Jellyfish, and more. The built-in tools include a ball-of-string notes system and color palettes to customize solving, plus achievements and leaderboards to measure your skill. Designed for beginners to experts, it provides a rich, portable brain-training experience that can be enjoyed anywhere.