Learn English your brain actually remembers.
Bite-sized lessons, spaced-repetition flashcards, and real reading & video — on your laptop or your phone. Five minutes a day is all it takes to make it stick.
Learn English from the things you already love
No fixed course, no textbook. Bring your own books, articles and videos — and turn every word into vocabulary you keep.
Read anything you actually want to read
Upload a book (EPUB, PDF), import any web article, paste your own text, or watch a YouTube video. No fixed course, no textbook — your content.
Tap a word, get its meanings
Not one translation. Every sense the word has, each with its own CEFR level, so you see which meanings are beginner and which are advanced. Pick the one you met.
Hear it, word by word
Natural narration with every word highlighted as it's spoken — karaoke-style. Read and listen together, which is how listening comprehension actually gets built.
YouTube with a real dictionary attached
Synced subtitles you can tap. Turn any video into a lesson.
Turn a book into a deck
See every word in what you're reading, ranked by how often it appears. Save what matters, build cards, study them.
Study without ceremony
Flashcards with your own pacing and autoplay, plus matching and pairing games for review.
Three steps to a daily habit
Don't just take our word for it
“I've tried every app out there. This is the first one where the words actually stuck. The flashcards feel like magic.”
“Reading real stories and tapping words to save them changed everything. I read a whole English news article last week!”
“The streaks got me hooked and Cortex is adorable. 60 days in and I finally follow my favorite English shows without subtitles.”
Real screens from the app
Your first word is 30 seconds away
Free to start. No credit card. Learn on iOS, Android, or the web.