A free app for Android, by C.C.T Games.

Sudoku Friends is an amazing logic-based number puzzle. It will challenge your brain and improve your logical thinking. You will start from easy levels and work your way up to expert level puzzles. It has 4 difficulty modes that are easy, medium, hard, and expert. 

You can play against other players worldwide or solve the daily challenges. There are daily puzzles that you need to solve to get the trophy. 

There are many levels that you can work on, and you can see how you are doing in the game. You will get the hint if you don’t know what to do. You can also work on the puzzle in the offline mode.