About Ultimate Sudoku

A puzzle game from Japan that has conquered the whole world.

Fill in the empty cells with numbers from 1 to 9.

In each row, column, or 3x3 block, each number can occur only once.

3 different game modes:

- Cell first: First click on the cell you want to fill in, and then select a number.

- Number First: first click on the number, and then on the cell in which you want to enter this number.

- Note Mode: Write down the option in an empty space using the keyboard or the number buttons.