DuoCards - Vocabulary Builder

Contains adsIn-app purchases
57.5K reviews
Content rating
PEGI 3
5M+
Downloads
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About this app

Build vocabulary and learn languages with DuoCards, a flexible vocabulary builder for English and 50+ languages. Save new words from videos, articles, subtitles, courses, then practice with AI flashcards, speaking exercises, listening practice, and spaced repetition so the words stay in memory.

DuoCards is built for learners who want more than generic language lessons. You can discover useful words in real content, save them into a personal vocabulary deck, and review them with smart language flashcards that adapt to your progress.

What you can do with DuoCards:

- Build English vocabulary with flashcards that repeat at the right time
- Learn words from videos, subtitles, articles, courses, and shared decks
- Practice conversations with an AI language tutor for daily situations
- Improve pronunciation with speaking and listening exercises
- Save phrases, example sentences, and translations in one vocabulary app
- Study Spanish, French, German, Japanese, Korean, Italian, Portuguese, Russian, and more
- Create private decks or learn from public vocabulary sets made by other learners
- Use offline learning when you want to review without a stable connection

Learn from videos and articles

Language learning works better when words appear in context. DuoCards lets you save vocabulary from videos with subtitles and from foreign language articles, so you can connect each word with a real sentence, topic, and memory. Tap a word, check the translation, save it to your deck, and review it later.

Practice with AI flashcards

DuoCards combines classic flashcards with AI practice. Review words, listen to pronunciation, speak your answers, ask for examples, and practice short conversations. Use the AI tutor to understand grammar, see words in context, and turn your saved vocabulary into useful phrases.

A vocabulary builder for many goals

Use DuoCards as an English vocabulary app, a Spanish flashcards app, a language flashcards app, or a daily vocabulary builder for school, travel, work, exams, and everyday conversations. You can learn beginner words, advanced phrases, useful verbs, pronunciation, listening, and sentence patterns.

How DuoCards works:

1. Choose the language you want to learn.
2. Find useful words in videos, articles, courses, decks, or your own notes.
3. Save words and phrases to your personal vocabulary deck.
4. Practice with flashcards, AI conversations, pronunciation, and listening.
5. Review with spaced repetition until the words become familiar.

Why learners use DuoCards:

- Real content: learn from videos, articles, and examples instead of isolated word lists
- Smart review: spaced repetition helps you remember vocabulary for longer
- AI practice: turn saved words into conversations, stories, and grammar examples
- Flexible decks: create your own word lists or study public language sets
- Many languages: learn English and 50+ languages from one app
- Clear progress: see which words are new, known, or ready to review
- Offline review: keep practicing vocabulary while traveling or commuting

DuoCards is useful if you are learning English, improving Spanish vocabulary, studying French words, reviewing German phrases, practicing Japanese or Korean, or building a personal word bank in another language. It works for beginners who need simple vocabulary and for advanced learners who want to remember words from real content.

Use DuoCards for:

- English vocabulary and pronunciation practice
- Spanish, French, German, Italian, Portuguese, Russian, Japanese, and Korean words
- Language flashcards with spaced repetition
- AI tutor practice for speaking and grammar
- Video lessons, subtitles, and article-based learning
- Personal word lists, shared decks, and ready-made courses
- Daily review sessions for school, travel, work, or conversation

Download DuoCards and build vocabulary from real content. Learn languages with AI flashcards, video lessons, articles, speaking practice, listening exercises every day.
Build vocabulary with AI flashcards and video lessons
Updated on
Aug 31, 2026

Data safety

Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region, and age. The developer provided this information and may update it over time.
  • This app may share these data types with third parties
    App activity
  • This app may collect these data types
    Personal info, Financial info and 3 others
  • Data is encrypted in transit
  • You can request that data be deleted

Ratings and reviews

55.5K reviews
László Mohácsi
September 8, 2026
I am close to regretting the one year subscription.. The app is basically good, but it is ridiculous that the import of my English -Hungarian own words list takes ages, since You can only import 20 lines at a time! Furthermore it is not possible to add a set of cards with one click, first You have to review all the cards one by one! Tremendous time waster. The words list in the library should be more structured to find the one material You're after. TOEFL/Oxford words list not really to find
Did you find this helpful?
DuoCards
September 11, 2026
Hi László! We're sorry to hear about the import and organization issues. It should now be possible to import a much larger number of words; we have sent them an update. Please try it again and let us know if something doesn't look right through the app help. Jana from DuoCards
Marcell Nagy
May 17, 2026
I have been using this application for years by now. Some of its translations and explanations have needed to be double-checked (my native language is Hungarian), However, I have learned more than 1700 words with this application. Nevertheless, there is still room for improvement. For example: adding spelling tests would be a great idea.
6 people found this review helpful
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DuoCards
May 21, 2026
Marcell, that's fantastic progress! We're thrilled to see you've mastered so many words. Your suggestions are valuable. 💪 Cheers, Jana from DuoCards
Fanni Báble
April 19, 2024
The best app I have found for pure spaced repetition vocabulary learning. Unfortunately, the AI gives glaringly incorrect explanations at least in my first language (Hungarian). I put in some suggestions to fix mistakes but there are a lot of them and frankly, I'm not paying for the privilege to work for the developers. I wish it wasn't in the app, it does more harm than good to people who don't already have a solid foundation in the language they're learning.
3 people found this review helpful
Did you find this helpful?
DuoCards
April 22, 2024
Hi Fanni, sorry to hear this! Please let us know which course or set it was at info@duocards.com. We will do our best to fix it! Michaela from DuoCards

What’s new

Learn more wherever you are with reliable offline study and syncing. Create personalized card sets with AI, get detailed pronunciation feedback, and practice with richer roleplays and comprehension exercises. We also added language-level progress, mobile deck export, and easier set search—plus many fixes and performance improvements.