Design
Seven real places in Japan, one per level.
A1 starts in spring mist in the Kiso Valley. The weather turns harsher with each level, up to Fuji in winter.


Engine
FSRS-5 spaced repetition over 4,400+ words.
Flip the card, then swipe: Got it or Again. FSRS-5 picks the day the word comes back, and a slow pass returns once more in the same session.


Offline
Works with no connection at all.
Every word and review lives in IndexedDB on the phone. A level downloads again only when its content changes, and reviews sync to the server after each session.
No account needed. An email sign-in backs up progress.
