Privacy Policy
mathru.net (the "Operator") handles user information in the smartphone app "NANSURU" and its related services (the "Service") as described below, in accordance with the Act on the Protection of Personal Information and other laws and regulations.
Effective date: October 24, 2026
1. Information We Collect
| Information | Details |
|---|---|
| Account information | Information required for authentication, such as the user ID issued upon login with Apple, Google, or other providers, and email address |
| Profile | Nickname, profile image, date of birth, gender, self-introduction, active hours, days off, language, and time zone |
| Fortune results | Generated fortunes, action guidelines, and generation progress |
| AI consultations | Consultation content and answers, and AI usage (number of tokens and estimated cost) |
| Purchase information | Paid plan products, purchase, renewal, and cancellation status, store transaction IDs, and receipts |
| Device and usage information | Device type, OS, app version, usage, crash and performance records, advertising identifier (if permitted), and IP address |
2. Purposes of Use
- To create and provide fortune results, action guidelines, and AI answers
- To authenticate and manage accounts, and to provide paid plans and verify purchases
- To prevent fraudulent use, investigate failures, and improve quality and features
- To display advertisements (personalized advertisements, if permitted)
- To respond to inquiries and to send important notices
3. Generation by AI
Fortune results are created with Google's Gemini API based on date of birth, gender, language, and the date. Results for the same date of birth, gender, and language are stored in a form that does not identify the user and are reused when generating results for other users. The content of AI consultations is sent to Google (Firebase AI Logic) to create answers.
4. Outsourcing to External Services and Transfers Outside Japan
To the extent necessary to provide the Service, the Operator entrusts the handling of information to the following businesses. Because these businesses have servers outside Japan, information may be stored and processed in the United States and other countries.
| Business | Main purpose |
|---|---|
| Google LLC (United States) | Firebase Authentication (login), Firebase Analytics, Crashlytics, and Performance Monitoring (usage analysis and failure investigation), Remote Config, App Check, Gemini API and Firebase AI Logic (generation of fortunes and AI consultations), AdMob (advertising) |
| Cloudflare, Inc. (United States) | Server processing (Workers), storage of profile images (R2), website delivery (Pages) |
| Turso (ChiselStrike, Inc., United States) | Storage of profiles, fortune results, and AI usage (database in the Tokyo region) |
| PingCAP, Inc. (TiDB Cloud, United States) | Storage of purchase status and of a cache of fortune results that does not identify users (United States region) |
| Apple Inc. and Google LLC (United States) | Payment and verification of in-app purchases |
Information on the personal information protection systems of each country is available on the website of the Personal Information Protection Commission of Japan. The Operator confirms that its contractors take appropriate security control measures.
5. Provision to Third Parties
The Operator does not provide personal information to third parties except where required by laws and regulations, where the user has consented, or where entrusted as described in the preceding section.
6. Advertising and Analytics
The Service displays advertisements from Google AdMob. On iOS, the advertising identifier is used for personalized advertising only if permission is granted through App Tracking Transparency. This permission can be changed at any time in the device settings.
7. Retention Period and Deletion
- Profiles, fortune results, AI usage, and profile images are retained until the account is deleted.
- When an account is deleted, this information and the login information are deleted. For details, please see Account Deletion.
- Purchase records are retained for the period required by laws and regulations for accounting, tax, and fraud prevention purposes.
- Usage analysis and failure records are retained for the period specified by each service.
8. Security Measures
We take measures to prevent the leakage or loss of information, such as encryption of communications, restriction of access permissions, and separation of databases for each user.
9. Requests for Disclosure, Correction, Deletion, etc.
Users may request the disclosure, correction, suspension of use, or deletion of their personal information. Profiles can be changed or deleted in the app. For other requests, please contact the point of contact below. We will respond in accordance with laws and regulations after verifying your identity.
10. Minor Users
Minors should use the Service after obtaining the consent of a legal representative, such as a parent or guardian.
11. Changes to This Policy
The Operator will change this Policy as necessary. Users will be notified of important changes in the app or by other means.
12. Contact
mathru.net
Email: [email protected]
This English version is a translation provided for reference. In the event of any discrepancy between this version and the Japanese version, the Japanese version shall prevail.