Co-Sudoku Makes Sudoku a Group Activity

Field notes

Co-Sudoku assigns each participant a color and leaves that color on every cell they place, turning a finished grid into a record of the solve. The daily mode uses a shared puzzle and ranks accuracy before time, while the coach offers written walks at any depth and three spoken walks per day in six listed languages for free. Paper puzzles can be scanned on-device, and the page describes continuity between iPhone and iPad through iCloud.