Open Sudoku Classic!, tap the 'New Game' button, then select your desired difficulty level from the options provided.

Yes, you can change the difficulty before starting a new puzzle or during gameplay via the menu, depending on game mode availability.

Features include hints, duplicate highlighting, notes, and auto-check, which you can enable or disable in the game settings.

Tap the 'Hints' button during gameplay to receive guidance on difficult cells, helping you progress when stuck.

Tap on a cell, then enable notes mode; input possible numbers, which update automatically as you fill in the puzzle.

Yes, go to Settings > Membership & Subscriptions to view or manage your paid features and subscription plans.

The app offers optional in-app purchases such as hints, extra puzzles, or ad removal, available through the in-app store.

Yes, Sudoku Classic! offers free puzzles to try, and you can explore basic features without a subscription.

Try restarting your device, updating the app to the latest version, or reinstalling it from the app store for optimal performance.