Master chess openings, build your personalized repertoire, and hone your opening skills with this comprehensive app.

Key Features:

• Extensive Opening Database: Explore a vast chess opening tree with detailed game statistics, powered by the Encyclopedia of Chess Openings (ECO). Compare ECO classifications and opening tree moves side-by-side.
• Repertoire Builder: Create and customize your own opening repertoire, adding, editing, and annotating moves with comments. The app automatically classifies move sequences using the ECO system.
• Interactive Trainer: Memorize opening variations efficiently. Train on white's, black's, or both sides' moves, including multiple variations simultaneously against randomly selected opponent moves from your repertoire. Set custom starting positions and track your progress.
• Import/Export: Export your openings in PGN format. (PRO version unlocks PGN import).
• Customizable Interface: Adjust chessboard colors and pieces, and enjoy dark mode support.
• Offline Functionality: Works completely offline, perfect for practice anywhere.

Learn popular openings like the Queen's Gambit and King's Indian Defense, and many more!

App Sections:

• Opening Explorer: Search the ECO or browse the opening tree. Easily switch between exploration features at any point in the game.
• Repertoire Management: Add your favorite opening lines to your repertoire and organize them effectively. Edit opening names as needed.
• Opening Trainer: A streamlined trainer to memorize variations. Track your training statistics and refine your opening knowledge.

Upgrade to Chess Opener PRO for enhanced capabilities:

• Unlimited repertoire size and opening depth.
• A significantly larger opening tree with game statistics.
• Access to a database of 100+ grandmaster repertoires.
• Powerful chess engine analysis.
• PGN import functionality.