Chess Lab: Arasan AI Engine

Online multiplayer & analysis

Free · In‑App Purchases · Designed for iPad

Play chess with Arasan AI for free. Online play, web invites, and 30 AI levels. Review games with analysis and eval graphs. Remove ads via IAP. Chess Lab: Arasan AI Engine combines a world-class chess engine with a beautiful, intuitive interface. Whether you are a beginner looking to improve or an advanced player seeking serious analysis and competitive matches, this app brings everything together in one place. ▪ Play Instantly with “Web Invite” • No need to ask friends to download the app or create an account. • Generate an invite link, send it, and they can join instantly from any smartphone or PC browser. ▪ Versatile Game Modes • Online Multiplayer: Compete against players worldwide and climb the global leaderboards. • Web Invite Play: Seamless private matches via URL. • Offline CPU Battles: Train against the powerful Arasan AI with 40 adjustable strength levels. • Local 2-Player: Play face-to-face on a single device. ▪ In-Depth Analysis & Replays • Powered by Arasan: Built-in robust UCI engine delivers highly accurate evaluations and best-move calculations. • Real-Time Evaluation: Monitor the advantage bar and centipawn score/graph during your game. • Interactive History: Replay matches with step-by-step playback, fast-forward, and instant position jumping. • Visualized Insights: Automatically highlights significant evaluation drops (blunders) and color-codes long-thinking moves (Red/Yellow). ▪ Premium Board Experience • 2.5D & 2D Views: Switch between an immersive 2.5D perspective and a classic flat board. • Assistive Highlights: Clearly displays legal moves, captures, and checks to help prevent mistakes. • Full Promotion Support: Choose Queen, Rook, Bishop, or Knight when your pawn reaches the final rank. • Suspend & Resume: Automatically saves unfinished games so you can continue later. • Tactile Feedback: Smooth animations paired with high-quality haptics for a satisfying feel.

Ratings & Reviews

  • This app hasn’t received enough ratings or reviews to display an overview.

• Refined the settings screen layout for better usability. • Optimized internal ad delivery systems for improved app stability. • Minor bug fixes and performance improvements.

Version 2.0.4

The developer, koji ozono, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .

  • Data Used to Track You

    The following data may be used to track you across apps and websites owned by other companies:

    • Identifiers

  • Data Linked to You

    The following data may be collected and linked to your identity:

    • Identifiers
    • Usage Data

  • Data Not Linked to You

    The following data may be collected but it is not linked to your identity:

    • Diagnostics

Privacy practices may vary, for example, based on the features you use or your age. Learn More

Accessibility

The developer has not yet indicated which accessibility features this app supports. Learn More

Information

  • Seller
    • koji ozono
  • Size
    • 62.9 MB
  • Category
    • Board
  • Compatibility
    Requires iOS 17.6 or later.
    • iPhone
      Requires iOS 17.6 or later.
    • iPad
      Requires iPadOS 17.6 or later.
    • Mac
      Requires macOS 14.6 or later and a Mac with Apple M1 chip or later.
    • Apple Vision
      Requires visionOS 1.3 or later.
  • Languages
    • English and Japanese
  • Age Rating
    4+
  • In-App Purchases
    Yes
  • Copyright
    • ©2026 Koji Ozono
  • Developer Website
  • Privacy Policy
  • License Agreement

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