Support

No. DragonFish runs entirely offline. The AI engine, board recognition, and all game data are stored locally on your device. You only need a connection to download the app.

In the game screen, tap the brain icon in the toolbar to reveal the thinking-time bar. Use the − and + buttons to adjust from 1 to 10 seconds per move. The setting is saved automatically.

Tap "Chụp Bàn Cờ" from the home screen and take or upload a photo of a physical Xiangqi board. The app uses an on-device YOLOv8 model to detect pieces, then maps them to board coordinates. For best results, shoot from directly above with even lighting and minimal glare.

Board recognition is actively being improved. It works well on standard piece sets under good lighting, but may struggle with unusual piece designs, poor lighting, or extreme angles. We'd love your feedback if you encounter issues.

Yes. Tap the ← arrow in the toolbar to undo. In human-vs-computer mode, undo steps back two plies (your move and the engine's reply). Tap → to redo.

In either Train or Deep Analysis mode, tap the pencil (✏) icon in the toolbar to enter Position Edit mode. Drag pieces from the palette onto the board, or drag pieces already on the board to move or remove them. Tap Done when finished — the engine will analyse or play from your custom position.

DragonFish uses a state-of-the-art NNUE engine built specifically for Xiangqi (Chinese Chess). On a real iPhone it achieves around 78,000 nodes per second and reaches depth 17+ in 3 seconds. It is significantly stronger than any human player.

Hearts are the in-app currency used to start games. You begin with 10 hearts. Each game start costs 1 heart. You can earn more hearts by claiming your daily reward or by purchasing a heart package from the shop. The Engine Unlock and Unlimited Hearts packages also permanently remove the heart requirement.

On the main menu, tap the flag/language button in the top bar to cycle between available languages (English and Vietnamese).

Game history is stored locally on your device using iOS UserDefaults. It is never uploaded to any server. Uninstalling the app will permanently delete your history.