DEEP IN Get Deep In

The place where a language
stops feeling foreign.

Learn English the way children learn their first language.

Real English videos, explained word by word.

Download on the App Store Get it on Google Play

On a phone new to Deep In, your first library video is free for 24 hours after sign-up. No card.

A real screen recording from the app, in Ukrainian and shortened: her answers take a few seconds longer. An English interview plays above its transcript; each word lights up as it is said, with the line in Ukrainian under it. Holding the word “odds” pauses the video and opens its meaning in that sentence; a tap saves the word. Then Solomia explains it in Ukrainian and answers a follow-up question.

The method

Children don’t study a language. They live in it.

Deep In works the way they do, in four steps.

  1. 01Hear the real thingHow people actually talk, at their real speed.
  2. 02Understand it in the momentWhat it means here, not in a dictionary.
  3. 03Meet it again and againYour words come back until they’re yours.
  4. 04Say itTalk it over with Solomia, out loud.

01 · Watch

Watch real English. Stop translating in your head.

The phrases native speakers really use.

  1. Every word lights up as it’s said.
  2. Your language runs under each line.
  3. Tap a line to hear it again, or slow the video down.

What research finds

18studies

Captions under the voice help you follow and pick up new words, by a large margin.

Montero Perez, Van Den Noortgate & Desmet, 2013, System
The player: the video on top, the line being said with one word lit, and its Ukrainian translation under it.

02 · Go deeper

Stuck on something? Pause and go as deep as you want.

  1. Hold any word. The video waits, and you see what it means here, in your language.
  2. Save it, or ask Solomia. She’s the app’s AI and knows every word of the video.
  3. Go as deep as you like: synonyms and their shades, then practice it in a dialogue.

You’re here now

“I found that nothing in life is worthwhile unless you take risks.”

  • How else can you say this?
  • How do I say this formally, casually, and in slang?
  • Why this tense here?
  • Which words here are worth saving?
Ask in English or in your own language.

What research finds

1/3vs1/5

of new words kept when their meaning comes as you read, against without it.

Yanagisawa, Webb & Uchihara, 2020, Studies in Second Language Acquisition
A word card: worthwhile, its meaning in this sentence in Ukrainian, more meanings, the sentence, Ask Solomia and Save word.
A chat with Solomia about the video: English lines with Ukrainian explanations, the line you are on, and questions to ask.

03 · Practice

After the video, the words become yours.

  1. Tap a word you saved, then Practice.
  2. Pick how: examples, synonyms, a dialogue, or your own question.
  3. Type, or answer out loud.

What research finds

Recalling a word keeps it longer than rereading it, and reviews spread over days beat cramming.

Karpicke & Roediger, 2008, Science · Kim & Webb, 2022, Language Learning
Practice with Solomia: today’s word, get over the hump, and quick starts: more examples, synonyms, how common it is, dialogue, other meanings, your own.
Solomia’s answer: six ways to say get over the hump, from everyday to formal, each with its shade, and an example.

04 · Talk

Finished the video? Talk it over with Solomia.

Like with a friend who watched it too: the topic, what surprised you, what you think about it.

  1. In the AI tab, tap “Talk about a video, out loud” and pick what you watched. She starts the talk.
  2. Hold to speak; she answers with her voice. On Deep, call her live and just talk.
  3. On a live call, a word comes out wrong? She uses the right one in her reply, the way a friend would.

What research finds

28studies

of conversation practice with a partner: feedback during the talk helped learners learn words and grammar, and the gains lasted.

Mackey & Goo, 2007, a meta-analysis of studies with human partners

None of the studies cited tested Deep In itself.

A live voice call with Solomia: her droplet, I’m listening, and the mute and Done buttons.
A live call with Solomia, on Deep.

Inside the app

Everything inside Deep In.

The Deep In home: Add YouTube Video at the top, then the most recent videos and shorts.
A topic in the library: Documentaries, all 47 videos.
  • 1,402 real videos29 topics, long talks and shorts.
  • Your own videosPaste a YouTube link, on Basic and Deep.
  • Subtitles in two languagesWord by word, your language under each line.
  • The meaning in the momentHold a word to see what it means here.
  • SolomiaAsk her anything, in writing or out loud.
  • Your vocabularyWords from a video keep their sentence and moment.
  • Cards and practiceCards, stories, synonyms, dialogues.
  • RemindersYour words on your lock screen.

The library, measured

Real English is fast. That’s the point.

202

Words a minute

A late-night interview, 0:35 to 0:48: 44 words in 13.1 seconds, from “I gave her a ring” to “What do you want?”, one speaker, pauses included. Measured 4 Oct 2026.

4.0

Million words in the library

Every one synced to the voice that says it. Every one opens when you hold it.

Across 1,402 curated videos. Machine transcripts, synced word by word. Measured 4 Oct 2026.

160

Words a minute · median

A typical video runs at about 160 words a minute.

Median 159.6 across 1,110 curated videos over a minute long; shorts 179, across all 459. Words ÷ video length, so pauses count and the speech itself runs faster. Measured 4 Oct 2026.

505

Channels · 1,402 videos · 418 hours · 29 topics

The internet’s own English. Its biggest shelf is people talking.

    Curated videos only. A video can sit in more than one topic, so the shelves add up to more than 418 hours. The voices you learn from are the people in the videos. Measured 4 Oct 2026.

    What changes

    This is the English you’ll meet this week.

    • A late-night interview · 0:38

      “I love her so much. She is so game.”

      so game: up for anything

    • A late-night interview · 12:23

      “No. I can’t do it. No, I’m good. I’m good right now.”

      no, I’m good: a friendly “no, thanks”

    • A cooking show · 12:55

      “I don’t know, I’m just gonna wing it. See what happens.”

      wing it: do it with no plan, and improvise

    • A stand-up set · 4:05

      “You know how to sit on the fence? I don’t.”

      sit on the fence: stay undecided, not pick a side

    • A business short · 0:20

      “There is nothing wrong with that, if that’s your jam.”

      if that’s your jam: if that’s what you love

    • A science explainer · 14:53

      “Well, it’s a quirk of the math.”

      a quirk: an odd little feature

    • A business interview · 40:46

      “…apply this fabric and this color and call it a day.”

      call it a day: stop there, it’s done

    • A travel video · 19:20

      “But for what it’s worth, we have the Camino de Santiago…”

      for what it’s worth: this may or may not help, but here it is

    Real lines and timings from library videos. In the app, the meaning comes in your language.

    418 hours of real English, from 505 channels.

    Start with one video. It’s free for a day.

    Get Deep In Get Deep In
    QR code: opens Deep In in your phone's app store

    Get it on your phone.
    Scan with the camera.

    On a phone new to Deep In, your first library video is free for 24 hours after sign-up. No card.

    • Lite

      The library, word meanings, Solomia, cards and practice, voice messages.

    • Basic

      Everything in Lite, plus your own YouTube videos: up to 10 hours every 30 days.

    • Deep

      Everything in Basic, plus live voice calls with Solomia: up to 200 minutes a month, 10 minutes a call.

    Prices show in the app, in your currency. Plans and prices

    Questions

    What is Deep In?

    Deep In isn’t where you go to study a language. It’s where the internet becomes your language environment: an app for iPhone and Android with real English videos, every word lit as it’s said and your language under each line. Hold a word to see what it means there, and ask Solomia, an AI who has the whole video, why it was said that way.

    Is Deep In the same as Deepin Linux?

    No. They’re separate products from different companies, with no affiliation. Deep In (deepin.world) is an English-learning app built on real video. Deepin (deepin.org) is a Linux operating system.

    Who is Deep In for?

    People who know the basics of English, from school, university or an app like Duolingo, and want to live in it: follow people at the speed they talk, get the joke, keep up at work. If you can read English, start with whatever interests you. Your language runs under each line, and any word opens with a hold.

    Is Deep In free? What happens after the first video?

    Downloading is free. Sign in with Google or email (or Apple, on iPhone), with no card. On a phone new to Deep In, the first video you open in the library is free for 24 hours after you sign up. After that, or to open a second video, choose a plan: Lite, Basic or Deep. If you’ve never subscribed to Deep In, your plan can start with a 7-day free trial from the App Store or Google Play; the app shows whether it does, and the date it ends, before you confirm. The plan then renews at its price unless you cancel at least 24 hours before that date, in your store’s subscription settings or under Manage subscription in the app. Prices show in your currency on that screen, because they differ by country.

    Which videos can I watch?

    The library: 1,402 English videos from 505 channels, 418 hours across 29 topics, from interviews and podcasts to travel, history and comedy. On Basic and Deep you can also add your own YouTube links, up to 10 hours every 30 days. Some videos can’t be added or transcribed: over 2 h 15 min, with embedding turned off, age- or region-blocked, or with no speech.

    Which languages does it work in?

    You learn English. Meanings and translations come in your choice of 18 languages, picked when you sign up: Ukrainian, Russian, Spanish, French, German, Italian, Portuguese, Chinese, Japanese, Korean, Arabic, Turkish, Polish, Bulgarian, Dutch, Swedish, Hindi and Bengali. The app itself comes in 8: English, Ukrainian, Spanish, German, French, Polish, Portuguese and Russian.

    How is Solomia different from an AI chatbot?

    A chatbot starts from nothing. Solomia has the whole transcript of your video and the second you’re at, and she sees the words you’ve saved from it. Ask about a line and she tells you why it was said that way, what else would work, and who you can say it to. She’s an AI built on a large language model, and she’ll tell you so.

    What happens to my data?

    Your saved words, chats and watch history are kept with your account so Solomia can use them, and what you send her is processed by our AI providers to answer you. Notifications never include your chats. You can delete your account in the app’s settings. Details: Privacy Policy.

    Through a window at night, a woman on a sofa laughs at her phone.

    Until you forget it’s
    a foreign language.

    GO DEEPER.

    Deep into language. Deep into culture.
    Deep into ideas. Deep into the world.

    Download on the App Store Get it on Google Play
    QR code: opens Deep In in your phone's app store

    Deep In is a phone app.
    Scan to get it on iPhone or Android.

    First library video free for 24 hours after sign-up. No card.

    DEEP IN Live the language.