Privacy Policy

Last updated: August 19, 2026

Tsuzuku (the "Service") is an app and website (tsuzuku.app) operated by Kotaro Okuda (the "Operator") that turns your diary into manga. This policy explains what information the Service handles and how.

1. Information we collect

Diary content: the text, photos, voice, and video you record, and the manga generated from them
Protagonist setup: a face photo you may optionally register
Account information: an anonymous user ID; if you sign in with Apple or Google for data transfer, the linked identifier
Purchase information: your in-app purchase history via Apple (the Operator never receives credit card numbers or other payment details)
Notification token: the device token needed to deliver push notifications
Usage data: behavioral events such as screens viewed and features used (never the content of your diary — no text, photos, audio, or video)
Technical information: access logs kept to operate the Service

2. How we use it

Providing the Service, above all generating your manga
Managing purchases and credits, delivering notifications
Analyzing usage to improve the Service
Preventing abuse, improving quality, and responding to inquiries

3. AI processing

To generate manga, your diary content (text, photos, voice, video) is sent to and processed by external AI providers such as Google via their APIs. It is sent only for generation. The Operator never sells or shares your content with third parties for advertising purposes.

4. Publishing and sharing

When you set an issue to "link-only" or "public", people with the link — or everyone — can read it. You can change or withdraw publication at any time. The "read" seals pressed by readers are counted anonymously, and only the count reaches the author.

5. Third-party processors

Supabase (database and storage)
Cloudflare (hosting and bot protection)
Google (AI generation, push notifications, sign-in)
Apple (sign-in, in-app purchases)
RevenueCat (purchase management)

6. Storage and deletion

You can delete diary entries and manga in the app at any time. You can request deletion of your account and all data from the in-app settings or via the contact below; we delete it within a reasonable period. Backups kept for disaster recovery are purged on a rolling basis after deletion.

7. Tracking

The Service shows no behavioral advertising and does not track you across apps or websites.

8. Children

If you are under 13, please use the Service with a parent or guardian's consent.

9. Changes

This policy may be revised as needed. We will announce significant changes on the Service.

10. Contact

Operator: Kotaro Okuda
Contact: support@tsuzuku.app