DuoCards - Vocabulary Builder

Contains adsIn-app purchases
4.6
55.1K reviews
Content rating
USK: All ages
5M+
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Content rating
USK: All ages
Contents for Different Age Groups
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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.
Updated on
Jan 21, 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

53.2K reviews
Emil Kiesche
July 5, 2026
the idea of the app is great. but I used it like two years ago and it was a lot of fun. Now it's like all the other big language learning apps. full of ai learning slop. the free version sucks so much now. why do I need an abo for learning some flash cards. It's just for the greedy investors behind it to get a constant money flow. I just wanna have a local app for learning some vocabulary and find good new ones. This is just stupid. I'm switching to an open source version.
5 people found this review helpful
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DuoCards
July 9, 2026
Hello Emil, We understand your concerns. Subscriptions help us continuously improve the app and add new features. But you are still able to use the free version for your learning. Jana from DuoCards
Barbara Woitke
May 7, 2026
You have the ability to upload YouTube videos that include subtitles, and the application will then extract and display the text. With a single click, you can add any unfamiliar words to your learning list. This is an exceptional feature! The DuoCards Team has done a remarkable job! The best app for expanding your vocabulary.
Did you find this helpful?
DuoCards
May 7, 2026
Hi Barbara! Thanks for the feedback! Glad you find the video subtitle feature helpful for expanding your vocabulary. 🚀
James Turner
February 10, 2026
it is a pretty useful app for sure. love that you can make flashcards of whole sentences and it'll clearly speak them to you. They've got a lot of great courses also. Though I do feel it's a bit steep the premium price, when other apps that are similar to this. It's a one off payment which is usually cheaper than what they want for the year.
4 people found this review helpful
Did you find this helpful?
DuoCards
February 16, 2026
We’re happy you’re enjoying the app!

What’s new

AI Roleplay - Practice real-world conversations in simulated scenarios
AI Stories - Interactive stories with comprehension exercises
Bookmarks - Save your current progress in an article for later
Transliteration - Read Chinese, Arabic, Japanese scripts easily
Auto Dark Mode - Study comfortably day or night
Smarter Translations - Context-aware translations
AI Grammar Feedback - Accurate corrections with explanations