Last updated: May 9, 2026
These Terms of Service ("Terms") govern your use of Kotonoki, an iOS application and the related website. By creating an account or using the app you agree to these Terms. If you don't agree, please don't use the service.
You must be at least 13 years old to use Kotonoki (or the minimum age in your country, whichever is higher). If you're under the age of legal majority where you live, a parent or legal guardian must agree to these Terms on your behalf.
You're responsible for keeping your sign-in credentials safe and for activity under your account. If you sign in via Apple or Google, the security of those accounts is handled by Apple or Google respectively.
Kotonoki offers paid subscriptions on a monthly and yearly basis. Subscriptions auto-renew until cancelled. The current price is shown in the app before purchase and on this website.
New subscribers may be eligible for a 7-day free trial. During the trial you have full access to subscriber features. You can cancel any time during the trial in App Store settings — if you cancel before the trial ends, you won't be charged. If you don't cancel, your subscription begins automatically and you'll be charged at the renewal date.
Free accounts can open one already-generated lesson per day. Subscribers can open ready lessons without daily limits and can generate new lessons up to a per-month cap (currently 30; subject to adjustment). Trial subscribers may have a separate trial-period cap. The current limits are shown in the app and may be updated to keep service costs sustainable; we'll communicate material changes in advance.
You agree not to:
We reserve the right to suspend or terminate accounts that violate these Terms.
The Kotonoki name, app, branding, and original content are owned by us. AI-generated lessons in the app are produced for your personal learning use; they may incorporate factual references to public works (anime series, films) under fair-use principles. Show metadata is sourced from TMDB — Kotonoki uses the TMDB API but is not endorsed or certified by TMDB. Japanese subtitles are sourced from the open-licensed catalog at Jimaku.
You retain ownership of content you create (e.g., manually added vocabulary). You grant us a limited license to store and process it solely to operate the service.
Lessons, examples, translations, readings, romaji, and illustrations are generated automatically by artificial intelligence and may occasionally be inaccurate, incomplete, or inappropriate. This includes potentially wrong kanji readings, mismatched JLPT level tags, or imperfect translations. Kotonoki is a learning aid — not a substitute for human instruction or professional language services. Verify important information against authoritative sources (a dictionary, a teacher, a native speaker).
We strive for high uptime but don't guarantee that the service will be uninterrupted or error-free. We may perform maintenance, update features, or change parts of the service from time to time.
You may stop using Kotonoki and delete your account at any time (Profile → Delete Account inside the app). We may suspend or terminate accounts that violate these Terms or where required by law. Upon termination, your access ends and your account data is removed per our Privacy Policy.
The service is provided "as is" and "as available" without warranties of any kind, either express or implied, including merchantability, fitness for a particular purpose, and non-infringement.
To the maximum extent permitted by applicable law, Kotonoki and its operators are not liable for indirect, incidental, special, consequential, or punitive damages, or for any loss of profits, data, or goodwill, arising out of your use of the service. Our total aggregate liability for any claim related to the service will not exceed the amount you paid us in the twelve months preceding the claim.
Some jurisdictions don't allow these limitations — in such cases, our liability is limited to the smallest extent permitted by law.
We may update these Terms occasionally. The "Last updated" date at the top reflects the latest version. Continued use of the service after changes take effect means you accept the updated Terms.
These Terms are governed by the laws applicable at our place of operation, without regard to conflict-of-laws principles. If you're a consumer protected by mandatory local law in your country of residence, those protections still apply.
Questions about these Terms: kotonoki@addicted.design.
