Netboku is a vibrant Sudoku game specifically designed for the unique characteristics of netbooks.

The standard Sudoku rules apply: - Each board is split into 9x9 Cells, and 3x3 zones consisting of 9 cells. - Each zone, column and row must contain each number 1 through 9 only once. The board is completed by filling all the empty cells with the correct number. Each puzzle is a pure Sudoku with no guessing required.

The puzzle difficulty can be set from 1 (easiest) to 9 (hardest), the difficulty setting affects the number of empty cells the puzzle starts with. Level 9 has no extra clues and provides the most challenging puzzles. Notes can be used to store the possible numbers, the notes icon is usually represented as a pencil, while making moves is done with the pen. All the numbers 1 to 9 can be noted, and are placed around the cell, select a number again to remove its note.

From the in game options, the notes can be automatically filled for all empty cells. This can save a lot of time, although some people will prefer to keep the board neat. If you get stuck, then the hint button will perform the next possible move for you, but costs 60 seconds time penalty so try to use it sparingly if you're going for a new record. The training mode will make solving the puzzle much easier. The possible numbers are shown, and the notes are coloured to show which moves are valid.

The automatic notes feature coupled with the training mode means a puzzle can be solved very quickly, so it would be possible to do a whole puzzle in under 5 minutes!.

Netboku is controlled with the mouse and keyboard, click on a cell to select it, and click on the number pad to set the move. It's also possible to select cells with the cursor keys, and pressing the number on the keyboard will also set the cell value. Moves can be undone using Ctrl+Z. Progress is saved automatically, so you can simply quit the game, and continue from where you left off, just select Continue Game from the menu.