ChessCodex

ChessCodex

In-app purchases

About this app

ChessCodex is a chess study app focused on opening preparation and game exploration.
What you can do

Build and review your own opening repertoires
Study positions and move choices
Browse and search large collections of games (offline)
Filter games by common criteria (year, ECO, players, results, dataset)

Offline databases (optional downloads)
Some features (Games / Search / Filters) require downloading free offline chess databases from within the app.
You can choose which databases to download, and you can keep using repertoire and position study even without them.

Designed for study
Fast UI for navigating lines and variations
Notes per position (FEN)
Smooth download manager with progress and resume support

ChessCodex is currently in beta and will be improved over time.

What’s new

Fixed an issue where Premium access could remain active after a Google Play subscription was revoked or expired. Improved subscription status synchronization while preserving access during temporary network errors.