Chessable is a free app available on iPhone that is designed to improve your chess game. It offers hundreds of free chess courses, covering openings, endgames, tactics, and strategy, taught by world-class instructors and players such as Magnus Carlsen, Anish Giri, Judit Polgar, and more. The app combines instruction from the world's best players and coaches with the science of spaced repetition to improve your chess over the long term.

The app's MoveTrainer software automatically quizzes you when it's time to review the material, at longer and longer intervals, backed by science as one of the best ways to learn and remember. Chessable PRO members can also train offline, download course videos, and sync their progress with the server next time they're connected. The app also offers custom settings and the ability to collect XP and badges to show on your profile, providing you with the tools to optimize your study.

The Chessable app is available for free on iPhone, and Chessable PRO offers unlimited slots for free courses, offline training capability, and more perks. Monthly and yearly subscriptions for Chessable PRO are available in the app.