Japanese learning, one flashcard at a time
Beautiful flashcard apps to help you master hiragana, katakana, and kanji — available on iOS and Android.
What is koshilab?
koshilab builds educational flashcard apps designed to make learning Japanese fun and effective. Our apps use spaced repetition and intuitive card-based interfaces to help you build lasting literacy skills at your own pace. Every app is ad-free, privacy-first, and follows the official Japanese school curriculum.
Flashcard-Based Learning
Tap through beautifully designed flashcards that make memorization natural and engaging.
iOS & Android
Available on both platforms so you can practice on any device, anywhere.
Privacy First
No ads, no tracking, no social features. Your data stays on your device.
Learn at Your Own Pace
Progress is saved locally on your device. Review and advance through cards at a comfortable speed.
Our Apps
ひらカタ
Master hiragana and katakana with interactive flashcards. Flip, tap, and learn the 46 basic characters in each writing system — the essential first step in reading Japanese.
音訓 (一年生)
Flashcards for all 80 first-grade kanji. Each card shows the character, its on'yomi and kun'yomi readings, stroke count, and example words to build real vocabulary.
音訓 (二年生)
Flashcards for all 160 second-grade kanji. Continue building reading skills with cards covering every on'yomi, kun'yomi, and common vocabulary for each character.
How it works
Each flashcard presents a character with its readings and example vocabulary. Flip the card to test your knowledge, then swipe to move on.
Cards are organized by grade level following the official Japanese school curriculum, so learners build skills in the same order as native speakers.
Get in Touch
Have a question or feedback? We'd love to hear from you.