About
About Inku
Why an app for learning Japanese should feel like a notebook, not a game.
Inku is a Japanese flashcard app for iPhone and the web. It is made by a small team. This page exists because people who buy small software deserve to know who made it, and why.
What we are reacting to
I tried the usual apps. I used Duolingo for 89 days, then noticed I could pass a lesson without reading any of the Japanese. I switched to Anki and filled a deck with scraped vocabulary I never reviewed because the blank card flow felt like a second job. I tried a handful of paid apps that all wanted me to enroll in a system.
The pattern I kept hitting was the same. Apps that were designed to make me come back tomorrow were not designed to make me learn anything today. Streak flames. Heart lives. Notifications at 9:02 PM because that is when their data showed I was most likely to tap. The interface screamed, and the Japanese whispered.
I am almost forty. I do not want another app that thinks my attention is the product. I wanted something that treated me like an adult who has ten minutes and wants to use them well.
What Inku is
Inku is a calm Japanese flashcard app. It teaches 208 kana, 2,701 vocabulary cards across JLPT N5 through N1 and topic decks, 429 kanji, and 436 phrases in casual, polite, and travel packs. The main card library includes bundled pronunciation audio.
The review session is finite. You open the app, Inku shows you today: maybe 15 cards, maybe 25, depending on where you are in the schedule. You answer each one, and then you are done. The home screen tells you what happened and what is waiting for next time. There is no feed to scroll.
Scheduling is handled by FSRS (a modern spaced-repetition algorithm). It is the same math that makes Anki work. The difference is that in Inku you never see the math. You just see a small, warm stack of cards that will appear again when they need to.
What Inku is not
- It is not built around public leaderboards or loud pressure.
- It is not a chatbot. It will not generate cards for you on the fly.
- It is not an all-in-one Japanese platform. It will not teach you to read a novel. It will teach you enough that the other tools you use will make sense.
- It is not a social network. There is no profile, no leaderboard, no shareable score.
- It is not supported by ads or the sale of personal data.
iPhone, with care
Inku is an iPhone app. Android is not available yet. iPhone keeps the native design: haptics, widgets, system fonts.
If you use Android, email app@inkujapanese.com if you want to be notified when a native Android app exists.
How the app is built
The iPhone app is SwiftUI and SwiftData. It is local-first: your progress lives on that device. There is no account and no progress sync in v1.
Pronunciation is pre-recorded through ElevenLabs (the Shizuka voice) at build time. On iPhone the clips ship inside the app. In the browser they are loaded as local study audio. Furigana is pre-computed with kuromoji so every kanji has a rendered ruby reading.
iPhone subscriptions run through RevenueCat and Apple In-App Purchase. Web subscriptions run through RevenueCat Web Billing on a web-only catalog. Web Pro does not unlock iPhone, cannot be redeemed on iPhone, and iPhone Pro does not unlock web. Crash reporting uses Sentry. If you use Inku, those companies see the technical data described in the privacy policy. Nobody else sees anything.
Who is behind it
Inku is made by a small team in Calgary, Alberta, Canada.
Bao Hua writes on this site. A short bio and links live on the author page.
Credentials
- Adult Japanese learner since 2022
- Built Inku full-time from Calgary, Alberta
- 10+ years shipping software (iOS, web, internal tools)
- Personally writes and audits every guide on this site
We read every email to app@inkujapanese.com. A suggestion, a bug, a translation fix, or a question about something you tried — that is how you reach us.
Founding note
“The best software I have ever used feels like the person who made it left a small part of themselves in it. That is what I am trying to do with Inku.”
What we are building next
- Catalog quality. We are continuing to review and improve the current N5 through N1 vocabulary bundles.
- Kanji recognition mode. A separate practice flow for reading kanji without leaning on furigana.
- Widgets. A home-screen widget that shows today's review count, not a streak.
- iPad. Same app, more room to write kana with a finger or Apple Pencil.
- Sentence mining. Optional, opt-in, and done by you, not by me.
Thank you for reading this far. If you have been waiting for a Japanese app that respects your time, download Inku on iPhone, and keep the hiragana guide nearby as you get started.
Where to go next: How to learn Japanese from scratch · Inku vs Duolingo · Why I stopped using Anki