I'm building Duolingo for blackjack card counting. It's a Progressive Web App so you can install, learn, and practice cross-platform, and it is designed to combine a mastery-styled lesson plan (e.g. you can't move onto until you demonstrate mastery of the current lesson) along with exercises and tools for keeping the skills sharp. A complete novice should be able to pick it up and become a profitable blackjack player.

It also contains tools for scouting casinos, logging sessions, calculating effective profit-per-hour based on table rules, and other things a professional would need.

I'm in the process of polishing it up, and am aiming to launch Fall 2026. Current pricing plan is to be ~$10-15 per month for the pro tools, but provide the offline capabilities, lesson plan, and learning tools completely free without ads or weird gimmicks like a limited number of lessons or practice per day.