Knight & Castle

Knight & Castle helps you improve at chess by playing—and learning from—every move. Play offline against Stockfish, one of the strongest chess engines in the world. Choose a level from Beginner to Expert, review your moves instantly, and understand what to do better next time. FIVE LEVELS OF REAL CHESS • Play against Stockfish from Beginner to Expert • Play as White or Black • Full support for castling, en passant, promotion, checkmate, stalemate, and the 50-move rule • Play offline without an account or online opponent INSTANT MOVE REVIEW After each move, see whether it was a Best Move, Good Move, Inaccuracy, Mistake, or Blunder. You can also see the engine’s recommended move and compare it with your choice. An accuracy-focused review helps you understand the difference between simply losing a game and learning from it. ON-DEVICE AI COACH On supported devices, the AI Coach explains your moves in plain English: • Why your move worked or failed • What tactical idea was missed • What to focus on next • Themes such as forks, pins, and king safety The coach uses Apple’s on-device Foundation Models when available. Engine move grades remain available on all supported devices. POST-GAME SUMMARY Review the game after it ends: • Move count • Accuracy • Mistakes and blunders • The key moment that changed the game • The engine’s best alternative LEARNING MODE • Hints when you are stuck • Take-backs to try a different move • Move list to revisit any position • PGN export for further study A SIMPLE CHESS TRAINER Knight & Castle is made for: • Beginners learning the rules and basic tactics • Players who want a strong offline opponent • Chess players studying their mistakes • Anyone who wants to practice without an account or online matchmaking Designed for iPhone and iPad with smooth animations, legal-move highlights, check indicators, and optional board coordinates. Notes: • AI Coach comments require a device and OS version that support Apple Intelligence and on-device Foundation Models. • This app contains ads. • This app uses the open-source Stockfish chess engine under the GPLv3 license.