Sudoku - Puzzle & numbers game

Never again will you search for a pen and paper puzzle! Offering 4 levels of difficulty, an intuitive interface, and all the tools easily accessible, this Sudoku app is bound to become your preferred choice. Should your game be interrupted, simply exit Sudoku, and your puzzle will be saved exactly as it is.

Curious about how your Sudoku skills compare to others? Share your results with our servers to find out or join weekly Sudoku competitions.

Basic rules of Sudoku

- The Sudoku grid consists of 9x9 spaces.

- You can only use numbers 1 to 9.

- Each 3×3 square can only contain numbers 1 to 9.

- Each column can only contain numbers 1 to 9.

- Each row can only contain numbers 1 to 9.

- Each number in each 3×3 square, column or row can be used only once.

- The game ends when all Sudoku grids are filled with the correct numbers.

“Only empty squares” is a basic Sudoku solution

This solution is very simple and is based on the fact that each 3×3 square, row or column of the Sudoku board should contain numbers 1 to 9 and each number can be used only once in each 3×3 square, row or column.

If we see that there is only one available cell left in a 3×3 square, row or column, we have to figure out which number from 1 to 9 is missing and fill it in this empty cell:

FAQ

Q: Why do I have to provide this app access to my photos/videos etc?

A: The permission in question is needed to enable the "move-to-SD" functionality. The app doesn't make use of this permission for anything else.

Q: How do I pause a game in progress?

A: The game pauses automatically when minimized, exited, or switched over to another task, so there is really no need for a dedicated pause button.

Q: What's going on? I select a number to go into the cell, but the cell remains empty. Then, when I select the next cell, all of a sudden, the number winds up there.

A: This is a normal behavior in the "Digit First" entry mode. In this mode you select a number first (indicated by the enlarged digit), and then select boxes where that number is to be placed.

To switch to the "Cell First" mode, where you select a box first, then the number, press the button that looks like this: 123/#.

There is a setting, which determines which entry mode is on by default at the start of each puzzle. See Settings-Default digit entry mode.

Q: Why do I get incorrect puzzles?

A: This usually means one of two things:

   1) The puzzle is too hard and the next move is not immediately obvious. In this case, Menu-Hint may prove useful.

   2) You made a mistake in your logic and came to a point of contradiction, but since you expected the app to correct you in case of an error, you see this contradiction as app's fault. If this is the case, try validating the puzzle with Menu-Validate, or modify the settings to alert you to all types of logical errors. (See Settings-Helper as only the obvious errors are flagged by default).

If you did all this and still think the puzzle is invalid, please take a screen shot and post it to our Sudoku forum together with an explanation as to what makes you think it is invalid, and we will investigate.

Key features include:

- 4 levels of difficulty

- 3 input modes: "Digit first", "Cell first", popup

- Pencil marks (also known as Notes) with auto fill/erase option

- Various highlighting options for selected digits

- Show digit counts feature

- Auto-save function

- Unlimited Undo and Redo

- Logic-based intelligent hints

- Two levels of automatic error checks

- Submit results and monitor progress online

- Top scores and History tracking

- Real-time competitions

Sudoku is compatible with trackball, touch screen, and keyboard inputs.

Please note that this app contains ads. You can choose between in-game banners or interstitial ads displayed every three games. The screenshots exhibit gameplay with the full-screen ad style selected.

Please be informed that the INTERNET permission is necessary for competitions and uploading game results. The READ and WRITE_EXTERNAL_STORAGE permissions are required for move-to-SD functionality.

Enjoy the game!