Chess: AI Challenge

A focused chess app for offline play, pass-and-play matches, and interactive lessons. Challenge the single strongest on-device AI without a connection, or hand one device to a friend for a two-player game. Play a quick game on a commute, practise special rules offline, or reopen a saved record to study the move that changed the result. When connected, choose a cloud player from DeepSeek, Qwen, or Doubao; cloud games and result uploads are always opt-in. Features: • Offline AI chess with one strongest level and support for check, checkmate, stalemate, castling, en passant, and four promotion choices • Pass-and-play two-player games with free side selection • Chess Academy with 20 chapters and 115 interactive exercises; chapters 1–4 (35 exercises) are free, while chapters 5–20 unlock with AI Pass • Saved games, step-by-step replay, and practice from an earlier position • Basic replay is free; AI Pass unlocks advanced on-device analysis, training from real game records, and local progress saving • PGN import/export and FEN position import, with system sharing for records • Optional cloud games and seasonal leaderboards with separate offline and cloud results • Twelve interface languages and on-device game and lesson progress AI Pass is an auto-renewing monthly subscription with unlimited cloud games, no automatic ads, and advanced lessons in chapters 5–20. Payment is charged to your Apple Account when you confirm purchase; the current regional price is shown in the app and by the App Store before purchase. The subscription renews automatically unless cancelled in Apple Settings at least 24 hours before the current period ends. No social account is required. Offline games and lesson progress stay on your device by default. Cloud play sends the board state and anonymous session data needed to run the game. Joining public rankings requires separate consent. DeepSeek, Qwen, and Doubao are third-party AI services and are not officially affiliated with this app. Privacy Policy: https://chenghengsheng.top/app/6815095187/privacy.html Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/