To choose a difficulty level:
- Tap the gear icon in the top right corner.
- Select Game Mode.
- Enable the Choose Difficulty switch.
After that, you’ll be able to choose between 4 difficulty levels: easy, medium, hard, and expert.
Tap the New Game button on the main menu to start a new puzzle, and then select the difficulty level you want.
If you enable the Choose Difficulty option during the game, your progress won't be lost. You can disable this option anytime.