Subskills breaks 22 sports into the individual techniques people actually practise: 554 sub-skills, from the backhand clear in badminton to the Lucena position in chess. For each one it collects free tutorials from YouTube, TikTok and Instagram.

Every video is checked before it's listed: does it teach this exact technique, in this sport, and teach it well? About 45% don't make it. The rest are tagged beginner, intermediate or advanced, with a short note on what each covers, and the sub-skills of every sport are ordered into a learning path, so you know what to learn next.

Browsing is free and needs no account. The iPhone app adds watch-later and watched lists. The code is open source.