The Sudoku - Sudoku puzzle is a logic-based number game to train your brain. Challenge your brain with this fun and addictive game, which features thousands of unique puzzles to keep you entertained for hours. With five difficulty levels to choose from, you can start off as a beginner and work your way up to becoming a Sudoku master.     Features:        1. Daily Challenges - Complete Daily Challenges and collect trophies.         2. Pencil Mode - Turn on/ off pencil mode as you like. Each time you fill in a cell on the sudoku puzzle grid, your notes are automatically updated!  3. Highlight Duplicates to avoid repeating numbers in a row, column and block.         4. Tap and hold a number to lock it and you can use it for multiple cells         5. Use the free hint function when you are stuck.  6. Auto check - Find your mistakes and challenge yourself or use auto-check to see your mistakes in real-time         7. Unlimited undo & redo          8. Sudoku online & Sudoku o...