Capture Japanese words the moment you hear them — and never forget them.
A single-user app I built to learn Japanese while living in Japan: fast AI-assisted capture, the memory of where each word came from, new words every morning from AI friends, and spaced-repetition review.
It’s a private, single-account app (email allowlist) — this page is the tour.
Why I built it
This is how I used to learn: every new word from anime, manga, or daily life in Japan went into a paper notebook — kanji, furigana on top, an arrow, then whatever meaning came to mind, half English, half Indonesian.
It didn’t hold up. Every reading took a lookup, I forgot where I’d heard each word, and the pages never quizzed me — so I rarely flipped back.
tangocho keeps the notebook habit and does the slow parts: it fills in the reading and meanings, remembers the source, and tells me which words to review today.
The same word in tangocho
- EN
- foreshadowing
- ID
- petunjuk awal; memberi tanda
Capture 取り込む
Type a word; Jisho + Gemini auto-fill the reading, Indonesian & English meanings, and an example. Tag where you heard it.
Browse 一覧
Every word as a table or bento grid, with furigana. Filter by source, mastery, or what’s due. Tap for full detail.
Practice 復習
SM-2 spaced-repetition flashcards. Flip, rate forgot / hard / easy, and the app schedules the next review.
Speak 話す
See the meaning, say the word out loud. Speech recognition checks what it heard against the word, then plays the correct pronunciation so you can compare.
Friends 友達
Create AI characters — a casual friend, a polite coworker — with their own themes. Each day they mention 4 new words in a one-line message; keep the ones worth learning.
Reminders 通知
A push notification at 07:00 brings a friend’s line and what’s due today, so new words keep coming even on days I forget to open the app.
See it in action
Home · today’s words
What’s new 更新履歴
See all updates →Meet the omamori
A small pixel お守り with 守 on it now cheers when nothing is due for review, and holds up a card when the word list is empty.
Smarter morning notification
The 07:00 push now only counts words I haven’t answered yet — open the app after midnight and deal with the day’s words, and the morning push won’t repeat them.
Daily notification at 07:00
A web push every morning with a friend’s line and what’s due for review — including on the iPhone home-screen app.
How it’s built
A full-stack PWA on entirely free tiers. Words are auto-enriched by a Jisho → Gemini fallback pipeline, review scheduling uses a hand-implemented SM-2 algorithm, Speak mode runs entirely in the browser on the Web Speech API (recognition + Japanese text-to-speech, no audio stored). Daily friend words come from one Gemini call a day, checked against Jisho and deduplicated, and a Vercel cron + Web Push delivers them at 07:00. Every row is protected by Postgres row-level security with a single-user Google OAuth allowlist.