DuoCards - Vocabulary Builder

DuoCards

Contains adsIn-app purchases

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.

Ratings and reviews

I was very happy with the app because I use it to learn Chinese, but in the most recent update they removed the pinyin section, which was a huge help for knowing how to pronounce or write words if you're new to the language. The loss is very noticeable, and I'm thinking of switching apps since that feature gave this app a significant advantage over others.

This app would have been a clear five-star one, weren't it for the fact that it doesn't really realize its potential (I'm a subscriber). AI coupled with flashcards is a powerful combination, but grammar explanations all look the same (they should be more varied and complete) and examples are often repeating. The Listen feature is very powerful, but we should be able to filter by set of cards. This together with a better production of examples would be great. Looking forward to updates.

One of the best flashcard apps I've ever used! You can add your own flashcards, organize them into folders, and study them. A very good feature in my opinion is the generation of unique images for each flashcard: it makes it easier to memorize the words. I also like how AI was used in the app: it is a learning support, that suggests pointers on grammar rules and on translations or sentence examples. The streak system, with not just days but also points are rewards is also super motivating

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