Kakera
AI flashcards for hard words
Free · Designed for iPad. Not verified for macOS.
Hard words, one piece at a time. AI writes a card that explains each word; a memory model brings it back just before you'd forget. English and Japanese, with furigana.
Kakera (欠片, "fragment") is a flashcard app for the words that will not stick. Each card is one small piece of a language; reviewed at the right moments, the pieces add up to a whole.
REVIEW A WORD JUST BEFORE YOU WOULD FORGET IT
Every word keeps three numbers: how stable it is in your memory, how hard it is for you, and how likely you are to recall it today. Kakera schedules with FSRS-6, the open spaced-repetition model, and brings a word back when that chance falls to 90%. Each review you pass makes the gaps grow, from days to weeks. Each rating button tells you when the word will come back before you tap it.
A CARD THAT EXPLAINS THE WORD, NOT JUST TRANSLATES IT
Paste a list of words and Kakera writes a card for each one: the meaning in Chinese and in English, examples, where the word comes from, its parts, the words it is confused with, and the phrases it lives in. It runs on your own Claude or OpenAI API key, kept in the iPhone's Keychain. Pick any model your key can use.
JAPANESE, WITH THE READINGS ON TOP
Switch the deck to Japanese and every sentence carries furigana. Cards give the kana reading with its pitch accent, split the word into morae, and take the kanji apart. In a quiz, hiragana and katakana count as the same answer. English and Japanese keep separate decks; hide the readings once you no longer need them.
AND THE REST
• Pronunciation for every word, played as the card turns
• Quizzes after each session that feed the same schedule
• A daily story made of the words you just reviewed
• Stats: the forgetting curve, memory maturity, what will slip this week, and your streak
• Search, tags and notes of your own
• A home-screen widget and a daily reminder at the hour you pick
• Light and dark appearance
YOUR WORDS STAY YOURS
No account, nothing to sign up for. Kakera has no server of its own: your deck lives on your iPhone and syncs between your devices through your own private iCloud database. Your AI key goes only to the provider you chose, and only when a card is written.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
The developer, 延昭 刘, 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 Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- 延昭 刘
- Size
- 7.8 MB
- Category
- Education
- Compatibility
Requires iOS 17.0 or later.
- iPhone
Requires iOS 17.0 or later. - iPad
Requires iPadOS 17.0 or later. - Mac
Requires macOS 14.0 or later and a Mac with Apple M1 chip or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- © 2026 Yanzhao Liu