Kanzen · Legal documents

Terms and conditions of use

Terms applicable to the use of the Kanzen application, published by Ikigai Studio.

Last updated: 18 May 2026 · Version 1.0

1. Publisher

The Kanzen application ("the App") is published by:

Tom Piguet, sole proprietor, operating under the commercial name Ikigai Studio
55 avenue du Général de Gaulle, 60150 Longueil-Annel, France
SIRET: 904 611 175 00020
Contact: contact.ikigaistudio@gmail.com

2. Acceptance

By downloading, installing, or using the App, you unconditionally accept these Terms and Conditions of Use ("Terms"). If you do not accept these Terms, you must uninstall the App.

The Terms may be modified at any time. Any substantial modification will be notified within the App. Continued use after such notification constitutes acceptance.

3. Service description

Kanzen is a mobile (iOS and Android) and web application for learning Japanese kanji, built around:

  • a spaced-repetition system (SRS) with cloud-synchronized progress;
  • solo training modes (games, guided drawing, visual discrimination);
  • an asynchronous multiplayer mode ("Duel mode") with league ranking;
  • a community-shared mnemonics library;
  • social features (friends, public profiles).

An optional paid offering ("Kanzen Plus") unlocks access to the full content and advanced personalization.

4. Account creation

Using the App requires creating an account via:

  • email + password;
  • or Google sign-in (OAuth);
  • or Apple sign-in (Sign in with Apple, iOS only).

The user must be at least 13 years old to create an account. Minor users between 13 and 15 must obtain the prior consent of their legal representatives, in accordance with article 8 of the GDPR.

The user undertakes to provide accurate information and to preserve the confidentiality of their credentials. Any activity performed from the account is deemed to come from the account holder.

5. Account deletion

The user can delete their account at any time, free of charge and without justification, from:

Profile → Preferences → Account → Delete my account

Deletion triggers the definitive erasure within 30 days of:

  • personal data (email, username, hanko, friend code, banner);
  • SRS progress and duel history;
  • friend relationships;
  • personal mnemonics;
  • display preferences.

Mnemonics published to the community feed are anonymized (the link with their author is irreversibly dissociated) but may be kept if they have been adopted by other users, in order to preserve their learning experience.

The user can also request account deletion by email to contact.ikigaistudio@gmail.com. A dedicated page details the procedure: ikigaistudio.dev/kanzen/delete-account.

6. Kanzen Plus subscription

6.1 Subscription

The Kanzen Plus subscription is purchased via the Apple App Store or Google Play stores. Current prices are displayed in the App before validation and include all applicable taxes.

6.2 Automatic renewal

The subscription renews automatically at the end of each period, for an identical duration, unless deactivated at least 24 hours before the renewal date, from your corresponding store account:

  • iOS: Settings → [your name] → Subscriptions
  • Android: Google Play → Menu → Subscriptions

6.3 Free trial period

Any free trial period, when offered, automatically converts to a paid subscription at its end if not cancelled before that date.

6.4 Refunds

Refund requests are handled exclusively by the stores (Apple App Store or Google Play) under their own terms. The publisher has no technical capacity to issue direct refunds.

6.5 Right of withdrawal

In accordance with article L.221-28 1° of the French Consumer Code, by immediately accessing the digital content provided as part of the subscription, the user expressly waives their 14-day right of withdrawal.

7. User-published content

7.1 Community mnemonics

The user can publish mnemonic memos visible to other users. They warrant that these contents do not infringe any rights (copyright, neighbouring rights, privacy, image rights) and that they hold all necessary rights to publish them.

7.2 License granted

By publishing a public mnemonic, the user grants the publisher a free, non-exclusive, worldwide license, for the legal duration of protection of the content, authorizing the publisher to reproduce, display, translate, and distribute this memo as part of the App's operation, including in future versions and on any medium.

7.3 Prohibited content

The following contents are prohibited:

  • inciting hatred, violence, discrimination, or harassment;
  • pornographic, obscene, or shocking content;
  • promotional, advertising, or misleading content;
  • infringing third-party intellectual property rights;
  • revealing personal information about others without consent;
  • unrelated to learning kanji.

7.4 Moderation

The publisher applies self-regulated moderation based on community reports. Any user can report a memo via the dedicated button on the detail card.

The publisher reserves the right to remove any non-compliant content, without notice, and to suspend or terminate accounts in case of repeated breach of these Terms.

8. Availability and liability

The publisher strives to keep the App accessible 24/7 but does not guarantee uninterrupted availability nor absence of errors.

The publisher cannot be held liable for:

  • temporary interruptions for maintenance or updates;
  • malfunctions related to a third party (Apple, Google, Supabase, RevenueCat, network operators, internet providers);
  • data loss resulting from misuse by the user (voluntary account deletion, uninstallation, loss of access to the email account);
  • the quality, accuracy, or legality of content published by users;
  • indirect damages (loss of opportunity, moral damages).

The App is provided "as is," with no warranty as to its suitability for a particular use.

The publisher's potential liability, for all damages combined, cannot exceed the amounts actually paid by the user under their subscription over the last twelve (12) months.

9. Intellectual property

The publisher retains all intellectual property rights over:

  • the App, its source code, its interfaces;
  • the sumi-e illustrations, yokai, hanko, and other original graphic elements;
  • the educational game design (games, training modes, league system);
  • the Kanzen trademark and the Ikigai Studio commercial name.

Linguistic data (kanji, readings, vocabulary, stroke orders) comes from public sources under free licenses:

  • JMdict / JMnedict © Electronic Dictionary Research and Development Group (Creative Commons BY-SA 4.0 license);
  • KanjiVG © Ulrich Apel (Creative Commons BY-SA 3.0 license).

Any reproduction, representation, or exploitation of protected elements without prior written authorization is prohibited.

10. Personal data

The processing of personal data is described in detail in the Privacy policy.

11. Applicable law and jurisdiction

These Terms are governed by French law.

Any dispute relating to their formation, interpretation, or execution falls within the exclusive jurisdiction of the French courts, subject to mandatory provisions applicable to consumers.

In accordance with article L.612-1 of the French Consumer Code, in case of a dispute not resolved amicably, the consumer user may freely resort to a consumer mediator by accessing the European online dispute resolution platform: ec.europa.eu/consumers/odr.

12. Miscellaneous

If any provision of these Terms is held to be null or unenforceable, the other provisions retain their full effect.

The fact that the publisher does not invoke a breach of any provision shall not constitute a waiver of the benefit of that provision.

13. Contact

For any question regarding these Terms:

contact.ikigaistudio@gmail.com