“A tool that can do active recall if you know the right prompt is not the same as a tool built around it.”
NotebookLM is Google's, it's mostly free, and it can now generate flashcards, quizzes, mind maps and even a podcast-style audio overview of whatever you upload. On paper that sounds like it does everything Leurons does, plus more. So here's the honest version of where the two actually differ.
What NotebookLM is actually for
NotebookLM is a research assistant first. You upload sources, it grounds every answer in them and cites where it got it from, and the Studio panel can turn that material into a dozen different formats: audio, video, slides, a mind map, a quiz. It's built for someone digging through a pile of documents and trying to make sense of them, and it's genuinely good at that. The study features are a layer on top of a tool designed for research, not the reason the tool exists.
That's not a knock. A free, source-grounded assistant that can summarise 50 documents in one notebook is a real, useful thing. It's just built for a different job than getting you through Thursday's exam.
The gap: active recall exists, but you have to know to ask for it
Type the right prompt into NotebookLM's chat, something like "ask me one question at a time, wait for my answer, then grade it," and it will genuinely do a version of active recall. People have found this. It works.
But it's a workaround, not a feature. There's no tab for it, no mode selector, no memory of which concepts you've already been quizzed on across a session, and if you don't happen to know that prompt, you get the default behaviour instead: NotebookLM answering your questions for you, which is the opposite of what actually helps you remember something. The tool that requires you to already know the study technique in order to get it out of the AI isn't really teaching you the technique.
What we built instead
The AI tutor is a dedicated part of the site, not a chat window you have to steer. It asks you to explain a concept from memory, you type your answer, and it tells you specifically what you got right and what's missing, then asks a follow-up that pushes on the weak part of your explanation. Three modes built in: plain recall, Socratic questioning where it only asks and never tells you the answer, and teach-it-to-a-kid. You don't need to know a prompt for any of it. You open the tab.
Upload the same lecture slides and you also get a summary, flashcards and a practice quiz, all from that one upload, all in one place with the tutor rather than spread across a Studio panel of formats.
Where NotebookLM is still the better tool
If you're doing actual research, comparing claims across a dozen sources, or you want a 10-minute audio overview to listen to on the way to a lecture, NotebookLM does things Leurons was never built to do, and its free tier is genuinely generous. If your problem is "I have too many documents and no idea what's in them," start there.
Where the two split is the same place Quizlet did: anything you actually have to explain from memory, cold, the way an exam demands it. That's a narrower job than "research assistant," and it's the whole job Leurons is built around.
The honest summary
NotebookLM is a capable, mostly free research tool that added study features on top. Leurons is a study tool built from the ground up around one method: explaining something back and finding out what you actually know. Different tools for different moments, and the way to find out which one this moment needs is to upload the same lecture to both and see which kind of studying actually gets you through the exam.