Sudoku Master Pr gives you virtually unlimited number of Sudoku puzzles to solve right on your iPhone or iPad. There are 9 difficulty levels for the puzzles, with 1 the easiest and 9 the most difficult. You can select a comfortable difficulty level to play with. The last Sudoku game will be saved, so you can pause the game or leave the app and come back later to continue solving the puzzle whenever you are free. Your play time and number of mistakes will be recorded so that you can track your progress in developing Sudoku-solving skills. The app now has battle mode, where you and your friends/family can compete with each other on the same puzzle. The app is truly a good companion for travels or just passing time.