Privacy Policy

Last updated: June 2026

The short version: MJWinLog stores all your data locally on your device. We do not collect, store, or sell your personal information. The only time any data leaves your device is when you choose to use the optional image recognition feature, which sends your photo to Google's Gemini API for tile identification.

1. Information We Collect

MJWinLog does not require an account and does not collect personal information such as your name, email address, or location.

The only data that may leave your device is:

Photos you submit for image recognition — When you use the optional "Recognize" feature, the photo you select is sent to Google's Gemini API to identify mahjong tiles. This is the sole purpose of the transmission. We do not receive, store, or have access to this photo.

2. Data Stored on Your Device

All hand logs, pattern history, and statistics are stored locally on your device using standard iOS storage. This data never leaves your device and is not accessible to us. If you delete the App, this data is permanently removed.

3. Third-Party Services

Google Gemini API — When you use the image recognition feature, your photo is transmitted to Google's Gemini API for processing. Google's handling of that data is governed by Google's Privacy Policy. We do not control how Google processes data submitted to their API, and we encourage you to review their policy.

We do not use any advertising networks, analytics platforms, or other third-party data services.

4. How We Use Information

We do not collect personal information, so we do not use it for any purpose. Photos submitted for image recognition are used solely to return tile identification results to your device. We do not use your data for advertising, marketing, profiling, or any other purpose.

5. Data Sharing and Sale

We do not sell, rent, or share your personal information or usage data with any third party, except as described in Section 3 (Google Gemini API) for the sole purpose of image recognition.

6. Data Retention

Because all app data is stored locally on your device, you are in full control of your data at all times. We do not retain any copies of your data on external servers. Photos transmitted for image recognition are not stored by us after processing.

7. Children's Privacy

MJWinLog is not directed at children under the age of 13. We do not knowingly collect any information from children under 13. If you believe a child under 13 has used the App, please contact us via the support page.

8. Your Rights

Because MJWinLog does not collect or store personal data on our end, there is no account data for us to access, correct, or delete. All data is under your control on your device. You may delete all app data at any time by uninstalling MJWinLog.

9. Security

All communication between MJWinLog and the Google Gemini API is encrypted via HTTPS. We do not operate servers that store your data, which minimizes the risk of unauthorized access.

10. Changes to This Policy

We may update this Privacy Policy from time to time. Any changes will be posted on this page with a revised "Last updated" date. Continued use of the App after changes are posted constitutes your acceptance of the updated policy.

11. Contact Us

If you have questions or concerns about this Privacy Policy, please reach out via our support page.