• Review Classic games with move-quality summaries, key moments and step-by-step board replays. • Explore engine alternatives and clearer Pawnie explanations directly on the board. • Classic training and post-game review now use on-device Arasan analysis. • Adjust Classic computer strength, thinking time and search depth. • Learn the review controls with a guided help tour.

• Improved Classic chess layouts for iPhone Duo, open or closed and in portrait or landscape. • Larger boards, clearer player and clock placement, accessible move history and compact controls. • Better two-column learning screens and a Fourfold Plus presentation adapted to the open display. • Smoother layout changes when opening, closing or rotating iPhone Duo.

• Online play stays responsive during room updates, with clearer recovery guidance for connection and matchmaking problems. • Find draw offers in the game or status sheet; compact lists show progress, results, time control and move count when available. • Preview Academy, puzzles, Helper and Practice in the Fourfold Plus carousel, with clearer plan selection and purchase controls.

• Play Classic 8×8 chess alongside Fourfold’s spatial games. • Challenge the computer or take turns with a friend, with side and clock choices. • Create a private Classic room or find an opponent for untimed, 5-minute or 10-minute unassisted online play. • Review games with position estimates, compare moves, explore Study variations and import or share PGN. • Ask Pawnie for Classic guidance, rehearse moves and see captured pieces in both games. • Pawnie respects both players: if either turns it off, it stays off for that match without changing your saved preference. • Enjoy smoother game setup and Helper transitions, clearer Profile statistics and refined Pawnie onboarding. • Enjoy a fitted Classic board, dedicated settings and full match-result celebrations. • Enjoy Classic rules and controls in all eight supported app languages.

• Meet Pawnie, your animated chess-pawn companion, with a short hands-on setup. • Choose Pawnie’s look, animation and help level in Settings or Profile. • Restore the observatory in The Lost Signal, a twenty-chamber interactive prologue with guidance for new and experienced chess players. • Learn how 2D, 3D and 4D views connect through a short playable introduction. • Get contextual built-in help and optional reminders while you play. • See legal moves more clearly and use compact help actions. • Enjoy Pawnie, setup and story guidance in all eight supported app languages.

• Choose your opening with visual mini maps. • Explore the starting position in 2D, 3D or 4D before confirming a new game. • Enjoy a refined glass preview with distinct Start and Close controls. • Follow spatial boards more easily with clearer lines and selection rings.

• Build a daily practice habit with streaks and a Home screen streak indicator. • Explore 102 puzzles across five learning levels, including challenges that explain movement in 3D and 4D. • Free players can solve a set of three puzzles. Unfinished puzzles stay available; the next set opens the day after all three are solved. Fourfold Plus unlocks all puzzles. • Enjoy clearer Learn navigation, challenge results and promotion choices. • Catch up with a new What’s New screen that includes updates from versions you skipped.

Watch the new App Store preview to see 4D Chess in action. Gameplay and features are unchanged from version 0.4.

Version 0.4 adds an iPhone Duo layout pairing a flat 2D board with a spatial 3D/4D board. Switch sides without losing your selection. Home, Learn, Rules, and Profile, plus board-based lessons and studies, adapt to the Duo layout. Subscription options refresh more reliably. Other iPhones and iPads keep their existing layouts.

Updated age-rating information for our casual chess experience.

• Play online: create a private room, join by code or QR, or find an opponent. Choose untimed, 5-minute or 10-minute games. • Explore Fourfold Plus with monthly and yearly plans: Full helper, deeper analysis, personal practice and advanced 4D Academy exercises. • Revisit positions in Study, organise notes and collections, and follow your practice activity. • Discover expanded onboarding, animated 2D-to-4D examples, smoother piece movement and clearer game results. • Core games, online play, Quick helper and existing lessons remain free.

• Create a private player profile with Apple, Google, or guest sign-in. • Choose a display name and a chess avatar inspired by four-dimensional space. • Explore the expanded four-space 8×8 board. • Enjoy clearer board miniatures, refined layouts, and smoother perspective transitions. • Continue playing against the computer or with a friend on the same device, without an account.