Chess Lab vs ChessLab

Open the app and your last channel is right there. Catch world-class games in your spare moments, save the ones that catch your eye, and analyze them. Chess Lab: Arasan Engine brings a world-class chess engine and Lichess spectating together in one beautifully intuitive app. ▪ Play instantly with Web Invite ・No downloads or accounts needed for your opponent. ・Just send an invite link and they can join right from their phone or PC browser. ▪ Plenty of play modes ・Web Invite: quick private matches via URL. ・Offline vs CPU: play the powerful Arasan engine with 30 difficulty levels to practice at your pace. ・Local 2-player: face off on a single device. ▪ World chess on your phone. Lichess spectating ・Watch top-level games right in the app, just like watching TV or manga on your phone. ・Channel selection (Top Rated / Bullet / Blitz / Rapid / Classical), thumbnail/list views, and display counts (10/20/30). ・See the board, moves, clocks, playback controls, and end reason. Step back to revisit any move. ・Your last tab and channel reopen automatically, so the world's games are always moments away. ・Save games that catch your eye to History and turn them into your own study material. ▪ Rich analysis and replay ・Powered by Arasan: a robust UCI engine that computes accurate evaluations and best moves. ・Engine analysis: real-time eval bar and position graph during play. Recalculate saved games with Analyze Position and save the graph too. ・Interactive history: step through, fast-forward, or jump to any position. ・Visual insights: big evaluation swings (blunders) are highlighted automatically. Long thinks are color-coded (red/yellow) so you can see time management. ・PGN import: bring in external game data (PGN). ▪ A premium board experience ・2.5D & 2D views: switch between an immersive tilted 2.5D perspective and a classic 2D board. ・Piece design: choose between text pieces and detailed image pieces. ・Full promotion support: pick queen, rook, bishop, or knight precisely when promoting. ・Pause & resume: unfinished games are saved automatically and can be resumed later. ▪ A refreshed menu and settings ・The bottom menu now has three tabs: Match / History / Lichess. The header changes with the tab. ・Your selected tab is saved, so the same tab opens next time.

ChessLab is a complete chess companion for iPhone and iPad: play, analyze, train and experiment, with the Stockfish engine built in and without ever leaving the app. HUMAN OPPONENTS Nine characters played by Maia-3, a network trained on millions of human games: it does not look for the best move, it plays the one a human of that level would play, blunders included. Each has a style, a repertoire, a temperament, a portrait, and an adjustable level on the human scale. Or take on Stockfish itself, from beginner (~900 Elo) to maximum (~3190 Elo). With or without a clock. Hints, a warning before risky moves, and an evaluation bar can all be toggled on demand. TWO PLAYERS Play locally on the same device, with a "pass-and-play" mode that flips the pieces so both players read the board comfortably. ANALYZE Run a game or a position through Stockfish: move-by-move classification (inaccuracy, mistake, blunder, brilliant move…), an evaluation graph, best-move and opponent-threat arrows, and auto-play through the moves. Import by PGN, FEN, position editor, or photo scanner. OPENINGS Pick an opening and step through it move by move: every move is explained, the alternatives are offered, and colored arrows link the board to the move list. 58 hand-written openings (bilingual), all reviewed by the engine, with simplified spaced-repetition training to memorize them. THE ENDGAME CORNER 78 courses proven by endgame tablebases — the exact mathematical verdict: no taught move gives up a win, no recommended defence loses a draw. Nine families, from the opposition to famous studies. And free training: finish the position against best defence, where any move that preserves the verdict is accepted — not just the lesson's move. VARIANTS Chess960 (Fischer Random Chess): a randomly drawn starting position, one chosen by number, or one you compose yourself, with a full post-game analysis just like "Play" mode. Eleven more variants against the computer, each with its own analysis: King of the Hill, Three-Check, Horde, Racing Kings, Atomic, Antichess, Crazyhouse, Stolen Move (a token every 7 moves lets you play twice in a row), Duck Chess, Barricades and Random Barricades. YOUR OWN REPERTOIRES Import your openings as PGN, variations included, and drill them with the same system. Share a repertoire as a single file — no account, no server. What you already know about a position counts right away in the imported repertoire. PUZZLES Over 100,000 tactics puzzles from the Lichess database, filterable by rating and theme, plus puzzles generated automatically from your own mistakes in analysis. Spaced repetition and progress tracking included. LABORATORY Pit two Stockfish configurations against each other over a series of games to compare their strength, with an estimated Elo gap and confidence interval. EDITOR AND SCANNER Set up a position by hand, or scan it from a screenshot or a photo — review and correct the recognized position before playing or analyzing it. BUILT FOR IPAD Full-size board with move list, graph and MultiPV visible at once, keyboard and trackpad support, polished portrait and landscape layouts. iCLOUD SYNC (optional) Turn on iCloud sync in Settings so your games follow you across all your devices, via your private iCloud. No account to create, no ChessLab server. Off by default: the app works fully offline. PRIVACY Offline by default: no ChessLab server, no analytics, no ads. Your games and settings stay on your device. iCloud sync, if you enable it, uses your own private iCloud — your data is never shared with the developer. Fully bilingual, French and English. ChessLab embeds the Stockfish engine (GPLv3 license), the University of Toronto's Maia-3 network (AGPLv3 license) and free vector piece sets — cburnett (GPLv2+/CC BY-SA), chessnut (Apache 2.0) and merida (GPLv2+). Full source code and license notices are available from within the app (Settings → Licenses).