Inku Help Center

Download the iPhone app from the App Store. The iOS release requires iOS 18 or later and works on iPad in compatibility mode. Android is not available yet.

No. Inku is local-first. Your learning progress is stored on that iPhone or in that browser and does not sync in v1. A store account may handle a purchase, but it is not an Inku learning account.

Inku starts you with the hiragana deck. The first session shows 5 brand-new cards, each with a romaji prompt, the kana, the audio, and a writing trace. You answer Again, Hard, Good, or Easy on each. The session ends when those 5 cards are reviewed.

Most users finish a daily session in 8–15 minutes. The length depends on how many cards are due plus how many new cards you've added (default: 5 per day). The session ends when today's queue ends. There's no infinite feed.

Inku uses FSRS (Free Spaced Repetition Scheduler), the same modern algorithm Anki adopted in 2024. After each card, you grade your recall as Again, Hard, Good, or Easy. FSRS uses your grade and recall history to predict when you'll forget the card and surfaces it just before that moment.

Yes. Settings → Study → New Cards Per Day lets you set anywhere from 0 to 50. The default is 5. Going higher than 15 a day generally produces a review pile-up that hurts long-term retention.

Yes. Mark a known card 'Easy' on its first appearance and the scheduler will give it a long initial interval. You can also use Settings → Study → Suspend Card to permanently remove a card you don't want to see.

Again: you didn't recall it (the card returns soon). Hard: you got it but with effort (shorter next interval). Good: you recalled it cleanly (the standard next interval). Easy: you recalled it instantly (longer next interval). Grade honestly — the scheduler uses your grades to predict your forgetting curve.

Both. Each session starts with a small batch of new cards (usually 5) followed by reviews of cards due today. New cards get a learning phase before they enter the standard SRS interval ladder.

Tap the pencil icon on any kana card to enter trace mode. The screen shows the stroke order with numbered guides; you trace each stroke with your finger or Apple Pencil. The mode does not score your handwriting; it builds motor memory through repetition.

US plans are $49.99 per year or $3.99 per week. The yearly plan includes a 7-day trial. iPhone is billed through Apple In-App Purchase. Web is billed through RevenueCat Web Billing on web-only products. Those stores do not share entitlements: web Pro does not unlock iPhone, and iPhone Pro does not unlock web. There is no iOS redemption of a web purchase.

iPhone: open Settings → your name → Subscriptions → Inku → Cancel Subscription. Web: cancel through RevenueCat Web Billing in the web app, or email app@inkujapanese.com if you cannot find the billing controls. Cancel on the store where you paid; cancelling one does not cancel the other.

iPhone refunds go through Apple at reportaproblem.apple.com. Web refunds go through RevenueCat Web Billing or email app@inkujapanese.com. We cannot override a store decision.

Yes, on iPhone. Family Sharing is enabled for iPhone Pro, subject to Apple's rules. Web Pro is a separate RevenueCat Web Billing purchase and is not shared through Apple Family Sharing.

No. Web Pro stays on the browser where you paid. There is no redemption link, code, or account that unlocks the iPhone app from a web subscription, and an iPhone subscription does not unlock the web app.

208 kana, 2,701 vocabulary cards (2,461 JLPT from N5 through N1 plus 240 topic cards), 429 kanji, and 436 phrases across casual, polite, and travel packs. All 16 study bundles are unlocked from day one.

The main card library has bundled pronunciation audio recorded for the cards in that library. Smaller surfaces, including some sample sentences and niche phrases, fall back to your device's built-in Japanese voice when bundled audio isn't present.

The bundled main library audio uses ElevenLabs voice synthesis (Shizuka voice) recorded at build time and shipped inside the app. It is not your device's built-in TTS. System Japanese voice fallback is reserved for the small number of surfaces where bundled audio doesn't exist.

Yes. Inku includes 400+ kanji with guided lessons across N5-N3. Lessons cover readings, meanings, memory cues where helpful, and sample words, then move each character into the same flashcard review as the rest of your study. That is smaller than a 2,000+ kanji-focused curriculum such as WaniKani.

Yes. The current catalog includes vocabulary bundles for every JLPT level from N5 through N1. The JLPT does not publish official vocabulary lists, so these are curated study decks rather than claims of complete exam coverage.

Yes. Create a flashcard for a word you meet, save it, and bring it into your review flow alongside Inku's ready-made cards.

Anonymous diagnostics only. Crash reports go to Sentry without personal data, and RevenueCat manages subscription state. Your learning data — every card grade, every interval, every progress mark — stays on your device and is never uploaded.

No. Learning progress is stored locally on that iPhone or in that browser. There is no account or cloud sync in v1. Web progress and iPhone progress stay separate.

Currently no. Export is a roadmap item. If you need this urgently, email app@inkujapanese.com and we'll discuss your case.

No. There are no banner ads, interstitials, sponsored cards, or ad profiles.

Your learning data is removed with the app. Reinstalling starts a fresh deck. Your subscription continues unless you also cancel it through your app store.

Check your iPhone's silent switch (the side toggle) and volume. Inku respects the silent setting. If the side switch is off, audio plays normally; if it's on, audio is muted. If audio still doesn't work, force-quit the app and reopen.

No. FSRS handles late reviews gracefully — overdue cards just get scheduled appropriately when you next see them. The streak counter pauses; the underlying schedule does not.

FSRS schedules cards based on your individual grading history. Lower-than-expected due counts usually mean your grades have been consistently 'Good' or 'Easy', which pushes intervals out. This is the system working correctly.

Tap the flag icon at the top of any card to report it. The flag includes the card ID, your reported reason (typo, wrong audio, wrong meaning), and an optional comment. We review every flag personally.

Email app@inkujapanese.com. Bao (the founder) personally answers every email. Response time is typically within 1-2 business days, often same-day for urgent issues.