duiduidui!
Chinese dictionary + AI tutor
Only for iPhone
Free · In‑App Purchases · Designed for iPhone. Not verified for macOS.
iPhone
duiduidui! is the Chinese learning app that actually keeps up with you.
At its heart is a comprehensive Mandarin dictionary — over 200,000 words and phrases, with pinyin, natural-speech audio, and example sentences for every entry. It goes well beyond the textbook, covering modern vocabulary, colloquial speech, and the slang people actually use online and in everyday conversation. Look anything up, tap to hear it — and it all works offline, so your dictionary is with you on the subway, on a plane, or anywhere the signal drops.
But duiduidui! is more than a dictionary:
• Your own phrasebook — Star any word or phrase to build a personal phrasebook of favorites, always a tap away and ready to review whenever you want.
• AI tutor — Chat in Chinese or English with a patient tutor that explains grammar, corrects you gently, and answers "but why?" as many times as you need.
• Snap to translate — Point your camera at a sign, a menu, or handwriting and get an instant translation.
• Adaptive flashcards — The review system tracks what you actually know and steers you toward the cards you're ready to learn next — never too easy, never overwhelming.
• Real progress — Watch your vocabulary, streaks, and skill level grow, session by session.
How it works
duiduidui! learns your strengths and gaps as you study, then balances new words against review so you stay in the sweet spot for learning. The more you use it, the better it fits you.
Start with a 7-day full-access trial — the entire dictionary, the AI tutor, and adaptive flashcards, free for a week. No commitment up front.
Whether you're learning your first character or polishing toward fluency, duiduidui! grows with you. 对对对 — "right, right, right."
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Subscription details:
• After the free trial, duiduidui! offers Monthly ($12.99) and Annual ($89.99) subscriptions.
• Payment is charged to your Apple ID at confirmation of purchase.
• Subscriptions renew automatically unless canceled at least 24 hours before the end of the current period.
• Manage or cancel anytime in your Apple ID settings.
• Terms of Use: https://duiduidui.app/en/terms-of-service/
• Privacy Policy: https://duiduidui.app/en/privacy-policy/
What's New in 1.1.0
• Dictionary download now recovers from connection hiccups, shows progress, and says clearly when you're offline
• Starred words and review progress sync reliably, including after a reinstall or device switch
• Profile photos upload and appear for your study partners
• Fixed a crash when signing out and back in
• Fixed phone-number sign-in occasionally rejecting a valid number
• New setting: turn off content warnings on dictionary entries
• Flip-card controls now always respond
• Search and dictionary layout refinements
• Framework updates for performance
The developer, Red Thread Labs LLC, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Linked to You
The following data may be collected and linked to your identity:
- Purchases
- Contact Info
- User Content
- Search History
- Identifiers
- Usage Data
- Diagnostics
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Red Thread Labs LLC
- Size
- 116.2 MB
- Category
- Education
- Compatibility
Requires iOS 16.4 or later.
- iPhone
Requires iOS 16.4 or later. - Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
13+
- 13+
- Infrequent
Profanity or Crude Humor
Mature or Suggestive Themes
Alcohol, Tobacco, Drug Use or References
Sexual Content or Nudity
Contains
User-Generated Content
- In-App Purchases
Yes
- Monthly $12.99
- Annual $89.99
- Copyright
- © 2026 Red Thread Labs LLC