On-Core Sudoku

Challenge you brain! On-Core Sudoku: consists of a nine-by-nine grid with 9 inner squares. To solve Sudoku each inner square must have one of the numbers between 1 and 9. Each row and column must contain each number once. It features error checking, annotations (pencil marking), undo move(s) and more. On-Core Sudoku features: - Games are generated randomly so you will never play the same game twice. - The game has three difficulty levels: Easy, Medium and Hard plus a Custom option for custom games. - Each difficulty level has it's own timer so you can try to beat your best time at each level. - The game auto-saves so that you can return to it at any time. - Generate Symmetric or Non-Symmetric puzzles. - Error checking to show invalid entered numbers. - Annotate (pencil mark) a tile with one or more numbers. - Unlimited Undo or Redo moves. - Autofill option to automatically fill in all the possible annotations. - Option to enter custom games from sources such as newspapers, puzzle books, websites, etc. - Wirelessly send or receive custom games, via a local WiFi connection, to a friend or family member who also has Game Pack Volume 1 or On-Core Sudoku. - Sound effects can be turned on or off. - No internet connection is required because the games are on your iPhone or iPod Touch.