Learn English from the YouTube videos you already watch
If most of your English input already comes from YouTube — creators, interviews, vlogs, news, film clips — the hard part is not finding material. It is that the words you did not know scroll past and are gone thirty seconds later. Lanma is a mobile app that closes that gap: send a video to it from your phone, keep the words you did not know, and review them until they stay.
Why YouTube English tends not to stick
Watching in English is genuine input, and it does build listening. What it usually does not build is vocabulary you can produce, for three ordinary reasons:
- Nothing is captured. You hear an unfamiliar phrase, half-guess it from context, and keep watching. There is no record of it by the time the video ends.
- Looking words up interrupts the video. Pausing to open a dictionary breaks the thing that made you watch in the first place, so most people stop doing it.
- One exposure is not enough. Meeting a word once — even in vivid context — is rarely enough to recall it later. Words need to come back, spaced out over weeks.
Lanma is built around those three problems in that order: capture, without leaving your phone; a list you can prune to just the unfamiliar; and a review schedule that keeps bringing the words back.
How it works, step by step
1. Send the video to Lanma from the YouTube app
Lanma registers as a share target on both iPhone and Android. When a video has language worth keeping, tap Share in the YouTube app and choose Lanma. The link is handed straight over and the vocabulary screen opens with the URL already filled in. You can also paste a URL in by hand if you prefer, which is what you would do for a video you found on a laptop.
2. Choose the definition language and level
You set which language the meanings should be written in, so an English word set can have Korean, Japanese, Spanish, or another supported language on the meaning side. You also choose beginner, intermediate, or advanced, which shapes what counts as worth extracting.
3. Keep the words you did not know
Lanma reads the video’s transcript and pulls out the notable words and expressions in it — a thorough pass over the whole video, not a fixed top-ten. It then shows you the list so you can uncheck anything you already know. Words you marked as known on an earlier video are folded away automatically, so the more videos you run through Lanma, the closer the list sits to your actual gaps.
Each word arrives with a definition, an example sentence, and the context it appeared in, so you are studying the sense the speaker actually used — not the first entry in a dictionary.
4. Review until the words stay
The saved words become a normal Lanma word set. You can study them with flashcards, multiple-choice quizzes, and typing quizzes, hear them pronounced, and practise them in AI chat that works your own saved vocabulary into conversation and corrects your grammar as you go. Underneath, a 6-stage spaced repetition schedule decides when each word comes back — roughly a day, three days, a week, a month, three months, and beyond — pulling a word back to shorter intervals whenever you miss it.
You can read the mechanics of that schedule in full on the home page, which walks through the states, the grading, and the six mastery levels.
What if the video has no subtitles?
Lanma looks for a transcript in the language you are studying first. If the video has none, it will offer the other transcript languages the video does carry, or transcribe the audio itself — up to 30 minutes per video, counted against your plan’s monthly transcription minutes. Live streams, age-restricted videos, and region-blocked videos cannot be processed.
How this differs from other YouTube English tools
Most well-known tools in this space are desktop browser extensions that improve the moment of watching: dual subtitles, click-a-word dictionary popups, sentence replay. They are good at comprehension while the video plays, and they generally need a computer.
Lanma sits at the other end of the same problem. It assumes you are watching on a phone, and it optimises for what happens after the video — the retention half rather than the comprehension half:
- It is a phone app, not a desktop extension. The capture path is the YouTube share sheet you already have on your phone.
- You bring the videos. There is no curated lesson library to work through — any video with a transcript works, so the vocabulary comes from what you were going to watch anyway.
- The words outlive the video. A saved set is reviewed on a spaced-repetition schedule and reused in quizzes and AI chat, rather than being a lookup that disappears when the tab closes.
- It remembers what you already know. Words you have marked as known stop being offered on later videos.
Lanma also handles written English the same way: paste an article, blog post, or news page and it will build a set from that instead.
Who this suits
- Intermediate and advanced learners whose English input is already mostly YouTube, and who want that input to turn into vocabulary they can use.
- People who watch on a phone, in transit or in bed, and will not switch to a laptop to study a video.
- Learners preparing for exams or interviews who want vocabulary from real speech rather than a generic word list.
- Anyone who has tried making flashcards from videos by hand and stopped because it took longer than watching.
It suits you less well if you want subtitles annotated live as the video plays, or a graded, structured course. Lanma does not replace either of those.
What it costs
The free plan covers 3 YouTube vocabulary imports a month, up to 5 word sets, and unlimited study and quiz sessions. Pro ($4.99/month) raises YouTube imports to 75 a month and adds AI chat and Smart Review; Premium ($9.99/month) raises them to 300 and adds AI stories. No plan has ads. Full limits are on the pricing table.
Also available in 한국어.