Privacy Policy

Effective September 30, 2026

This policy describes how the “Eye'sTest” iOS app (視力チェック, the “App”), developed by Takeshi Kawai (the “Developer”), handles information.

1. Information we collect

To improve the App, we collect the following. None of it is linked to your identity (such as name or email address), and none of it is used for advertising or tracking.

• Usage data (Firebase Analytics): anonymous statistics about how the screens are used. No advertising identifier (IDFA) is collected.
• Crash data and diagnostics (Firebase Crashlytics): diagnostic information collected when the App unexpectedly quits.

2. Information stored on your device

Your viewing-distance setting (10–100 cm) is stored locally on your device and never transmitted. Crash data, once captured, is also buffered temporarily on the device and sent to Firebase on the next launch, after which it is removed from the device.

3. Information never stored or transmitted

Measurement results (your vision scores) are shown on screen only — they are never saved or sent anywhere. The App has no accounts and does not access photos, contacts, location, or other on-device information.

4. Third-party data processing

The collection in Section 1 uses Firebase, provided by Google LLC, and is processed under the Google Privacy Policy. Following this app's Firebase project retention settings (2 months for event data), usage-event data is automatically deleted 2 months after collection. We never sell or share collected data with any other third party.

5. Advertising

The App displays no ads, and no data is used for ad delivery.

6. Children

The App is intended for all ages and does not knowingly collect data requiring parental consent from minors.

7. Changes to this policy

Changes will be announced on this page; significant changes will also be noted in the App.

8. Contact

Questions about this policy: takezou621@gmail.com