FEATURES - Simple, beautiful and intuitive design. - Play on your Apple Watch, iPhone and iPad. - Thousands of puzzles to solve. - Play on a miniature 4x4 grid on your Apple Watch. - Play on a traditional 9x9 grid on your iPhone and iPad. - Keep your brain active when you have some time to kill. - High quality graphics. - No adverts. - Play Anywhere! HOW TO PLAY The objective is to fill the empty cells with numbers between 1 and 4 (Apple Watch) or 1 and 9 (iPhone and iPad), so that every row, column and block contains every number only once. Tap on the empty cells to change the values.