Privacy Policy

Last updated: March 2025

This Privacy Policy explains what data is collected when you use the Hydra app (the "App"), how it is used, and how it is protected. Hydra is designed with privacy in mind: your hydration records are stored primarily on your device and no account is required.

1. Data We Collect

Data stored locally (on your device)

The app stores the following data only in your local on-device database:

• Water and drink logs (amount, type, timestamp)
• Daily goal and unit preference (ml / oz)
• Reminder times and notification settings
• Streak and best streak information
• Custom drink types (Pro users)

This data does not leave your device. We do not transfer your hydration logs to our own servers.

Subscription and attribution data

In-app purchases are processed by Apple App Store or Google Play. We use RevenueCat to validate your subscription status. During this process:

• Your payment details (such as card numbers) are never sent to our app. They are handled only by Apple or Google.
• RevenueCat may generate an anonymous user identifier (randomly created) to verify purchase history and subscription state.
• On iOS, if you grant App Tracking Transparency (ATT) permission, device identifiers (for example IDFA / device identifier) may be used for subscription attribution and campaign performance measurement.
• If ATT permission is not granted, tracking-oriented device identifiers are not used on iOS.
• You can review RevenueCat's privacy policy at revenuecat.com/privacy.

2. Data We Do Not Collect

Hydra does not:

• Require account or profile creation
• Collect email addresses or phone numbers
• Request or use location data
• Collect usage analytics or crash reports
• Offer social login options

3. Notifications

If you want to use reminders, the app asks for system notification permission. This permission is used only to send scheduled reminders. No additional personal data is collected or transmitted for notifications. You can revoke this permission at any time from your device settings.

4. Data Security

All app data is stored in your operating system's secure storage layer (app sandbox on iOS, internal storage on Android). If your device is encrypted, this data is encrypted as well. Since hydration logs are not transmitted to our servers, no network transfer encryption is required for that data.

5. Data Retention and Deletion

Your data is retained as long as it remains on your device. You can remove data in two ways:

• Delete a single record: You can remove any individual hydration log in the app. This action cannot be undone later (except by tapping "Undo" immediately after deletion).
• Delete all data: Uninstalling the app permanently removes all local data. We do not provide cloud backup for this data, so deleted records cannot be restored.

6. Children's Privacy

Hydra is not directed to children under 13. Because we do not collect personal data, we do not perform special processing under COPPA-like frameworks. If we become aware that a child under 13 is using the app, we will take appropriate action.

7. Third-Party Links

The app and this website may contain links to external services such as Apple App Store or Google Play. We are not responsible for the privacy practices of those services. We recommend reviewing their privacy policies.

8. Changes to This Policy

We may update this Privacy Policy from time to time. If material changes are made, this page will be updated and the "Last updated" date will be revised. We may not always provide advance notice in-app or by email, so please review this page periodically.

9. Data Controller Contact

The person responsible for this app and this privacy policy is:

If you have questions or concerns about this policy, you can contact us via the email above.

We aim to respond to all privacy requests within 30 days.