Sudoku one + Easy to expert

More than 5000 grids of the best Sudoku available. Simple rules. For hours of play, whether you are a beginner, or an expert at Sudoku.
The rules of Sudoku are simple and can be learned in a few minutes.
Sudoku One offers 11 different game levels and 500 puzzles per level: It will probably take you more than a couple of thousands hours, and a lot of logic to get these 5500 puzzles finished.
Each puzzle has a unique solution. It is up to you to find it using your logic and perspicacity.
This version of Sudoku One allows you :
• To access all the 5500 Sudoku puzzles.
• To begin and progress, some puzzles have been specially designed for beginners. Their grids have been done specially for first-time players.
• To access grids of any level. The 11 game levels provide a smooth progression, from beginner to logic expert.
• Annotate the table, to record assumptions and move forward in complicated cases.
• To go back: there is a "UNDO" button to cancel up to 100 actions. Don't be afraid to test your assumptions anymore.
• To enjoy high definition graphics for maximum readability.
This version of Sudoku One adds unique features:
• An automatic deletion of unnecessary assumptions, when one of them is no longer logical.
• A help system, which offers you several possibilities:
• Check if you have errors in your grid, without showing them to you. This allows you to remove a doubt, without providing you with the solution.
• Show you where the mistakes are.
• Give you a hint, which will allow you to move forward in difficult cases.
Feel free to send me your comments (via the app) so that future versions will be even more attractive.