Privacy Policy - mizu:log

Last updated: May 27, 2026

This Privacy Policy describes how the mobile application "mizu:log" (the "App") handles user information.

1. Information We Collect

The App may collect the following information:

1-1. Information provided by users

Important:

This data is primarily stored locally on your device (e.g., using local databases such as Hive). However, when you use AI features (plant identification or diagnosis), photo data is transmitted to third-party servers (see Section 1-5).

1-2. Information collected by third-party services (Advertising)

The App uses Google AdMob provided by Google LLC to display advertisements. Google advertising networks and mediation partners may also be used to deliver ads. These third parties may automatically collect and use certain information, including:

Depending on your jurisdiction, this information may be considered personal information or personal data. It may be used for ad delivery, ad personalization, ad measurement, fraud prevention, and related purposes.

1-3. App usage analytics

The App uses Firebase Analytics provided by Google LLC to help us understand how the App is used and to improve its features. The following information may be automatically collected:

This information is used to understand app usage, improve quality, and investigate issues. The App does not transmit the contents of plant photos, diary text, or note text to servers for analytics purposes. However, when using AI features, photo data is transmitted to servers (see Section 1-5). However, some user-provided information, such as plant IDs or plant names, may be sent to Google as Firebase Analytics event parameters. For more details, please refer to the following Google policies:

1-4. External Communication for Recommended Items

The App displays recommended items for plant care. Product images are loaded from external servers (such as Rakuten CDN), which means your IP address and other connection information may be transmitted to those servers. Tapping an item link will open the product page in an external browser.

The App tracks impressions and taps on recommended items through Firebase Analytics (see Section 1-3).

1-5. Data Transmission for AI Features

The App provides AI plant identification and AI plant diagnosis features. When you use these features, the following information is transmitted to servers:

This information is sent via Firebase Cloud Functions (managed by the developer) to the OpenAI API provided by OpenAI, LLC, where it is used to generate identification or diagnosis results. Data sent to the OpenAI API is not used for model training, in accordance with OpenAI's API data usage policies.

The following information is stored on Firebase (Google LLC) in connection with AI features:

This information is used to manage usage limits and deliver diagnosis results. Anonymous authentication does not collect personal information such as email addresses or passwords.

1-6. In-App Purchase Verification

When you make a one-time purchase in the App, your purchase receipt is sent via Firebase Cloud Functions to Apple's servers to verify the transaction. The verification result (purchase status) is stored on Firebase.

2. Purpose of Use

We use the collected information for the following purposes:

  1. To provide app functionality (plant management and watering reminders)
  2. To improve app quality and fix issues
  3. To analyze app usage and improve features
  4. To deliver and optimize advertisements
  5. To recommend items useful for plant care
  6. To provide AI-powered plant identification and diagnosis results
  7. To verify in-app purchases and manage purchase status

3. Data Sharing

We do not sell your personal data.

However, as described above, third-party services such as Google may automatically collect certain technical information for advertising purposes. Firebase Analytics may also send app usage information to Google for analytics purposes. As described in Section 1-5, photo data may also be sent to OpenAI when using AI features. We may also disclose information if required by law.

4. International Data Transfers

Information collected through third-party services such as Google AdMob, Firebase Analytics, and the OpenAI API may be processed by Google LLC, OpenAI, LLC, their affiliates, advertising partners, and service providers in countries or regions outside your country of residence. Please refer to the privacy policies of those third-party service providers for details.

5. Data Retention

Data stored within the App remains on your device until you delete it or uninstall the App.

Information collected by third-party services such as Google AdMob and Firebase Analytics is retained in accordance with those service providers' policies.

6. User Control

6-1. Data Deletion

You can delete your data at any time using the in-app deletion features.

6-2. Ad Tracking

You can disable ad tracking (IDFA) through your device settings.

In regions where consent is required by applicable law, such as the European Economic Area (EEA), the United Kingdom, and Switzerland, consent for advertising or analytics may be required or provided through platform or third-party mechanisms.

7. Disclaimer

The App is intended to assist with plant care. The developer is not responsible for any damages, including plant loss, caused by missed notifications, app errors, or data loss. AI features (plant identification and diagnosis) provide reference information only and do not guarantee accuracy or completeness. The developer is not responsible for any damages to plants resulting from actions taken based on AI identification or diagnosis results.

8. Children's Privacy

The App is not directed to children under 13 and does not knowingly collect personal data from children.

9. Changes to This Policy

We may update this Privacy Policy from time to time. Changes will be posted on this page.

10. Contact

If you have any questions, please contact us: