Fill in the grid so that every row, column, and 3 x 3 box contains digits 1 through 9. That's all there is to it.
Really. There's no math involved, only logic.
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: What happened to all the functions that used to be available under the Menu?
A: They are still there, only on some of the newer devices the way to access the menu has changed. In most cases you need to long-press one of the buttons on the screen, like a "Recent Tasks" button
found on most new Samsung devices.
We are actively working on making Menu functionality easily accessible to you once again.
Q: The app is buggy and lagging. 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/#.
Additionally, 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: The app makes solving Sudoku too easy.
A: The app has some default settings set to suit the preferences of the majority of players. Feel free to modify the Settings to match your own solving preferences.
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.