Inku Help Center

Inku is available today through the App Store, and Android is in development. The current release requires iOS 18 or later and works on iPad in compatibility mode. Search 'Inku Japanese' or visit inkujapanese.com and tap the download button.

No. Inku is local-first. Your learning progress is stored on your device and never leaves it unless you explicitly export it. Your app store account handles purchases, 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.

Open iPhone Settings → tap your name at the top → Subscriptions → Inku → Cancel Subscription. Apple handles all subscription management; Inku has no separate billing portal.

Apple, not Inku, handles refund requests. Visit reportaproblem.apple.com within 90 days of purchase. Apple typically grants refunds for accidental purchases and unused subscriptions; we cannot override their decisions.

Yes. Family Sharing is enabled on Inku Pro. One person in your family group can purchase and the rest can use Inku without a separate subscription, subject to Apple's Family Sharing rules.

Kana practice, 2,461 JLPT vocabulary cards from N5 through N1, 240 topic cards, 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.

Not yet. Kanji currently appears on N5 and N4 cards in context with vocabulary. A dedicated kanji recognition mode (similar to WaniKani) is on the roadmap but not in the current release.

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 your device. Cloud sync is on the roadmap but not in the current release. For now, your device is the canonical store.

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.