RetainHQ keeps track of what you study and logs it for you automatically. Install the free RetainHQ Companion browser extension and the tutorials you watch, the docs you read, and the AI chats you learn from are turned into a study log on their own — no forms to fill in. You can also log anything by hand in a few seconds.
Then RetainHQ brings each topic back as a short quiz, timed to reach you right before you'd forget it, so what you study actually sticks. Your dashboard shows what you still remember, not just what you finished. Works for anything you're learning — DSA, system design, Python, C++, SQL, AI engineering, core CS, and school subjects.