At SudokuNoL, Sudokus can be entered conventionally, created by chance, or scanned in. The app distinguishes between a Startup mode and a Play mode. It can, but does not have to, be played in the different modes, but the advantage is that the default numbers are protected and can only be changed in the Startup mode. The solution is calculated in the background when the modes are switched and, if there is one, this is displayed on request. When looking for a solution, the program supports as much as you have set. Displaying the possible candidates, the next possible solution step or a possible cleanup of duplicate pairs is only one of many possibilities. Of course, every Sudoku can be saved. A connected database allows the assignment of names, comments, creation date and the level. This database can be changed at any time and sorted using these 4 criteria.