ZuDuKu Pro is a new kind of Sudoku game app for your Mac. 

The unique features of the app are:

1. You may play Sudoku games with numbers (1-9), interesting figures or letters (A-I).

2. It provides seven game levels with increasing difficulty to challenge your puzzle solving skills.

3. It provides sound effects to make playing games more interesting. You may turn-on/off sound effects at anytime.

4. It uses an advanced game generator and a solver to ensure each game has a unique solution.

5. It keeps track of your best scores, in term of game completion time and the number of errors committed, for each game level. Once you complete a game, the app will depict your game results and compared that to any previously recorded best result for the current game level.

6. Any wrong selection of keys will be flagged and rejected by the app. This ensues you will always complete each game.

7. Other user friendliness features: (a) tiles that need to be filled by you are highlighted in pale white or light gray color, so that you can locate them easily; (b) keys that are no longer needed in games are blanked out; (c) tiles that contain the last selected key are highlighted in cyan color.