Privacy Policy

1. Information We Collect

Profile & Onboarding Data

When you set up the app, we collect your name, age, weight (in lbs), activity level, wake and sleep times, and any health considerations you choose to share (such as whether you are pregnant or breastfeeding). We also store your preferred AI coaching personality. This information is used solely to calculate your personalised hydration goal and tailor in-app coaching messages.

Hydration Logs

Every water entry you log is stored on your device. Each entry includes the amount (fl oz), timestamp, drink type (e.g. water, coffee, herbal tea), an optional note, and whether it came from the app or Apple Health. This data is used to track your progress, calculate streaks, and generate coaching messages.

Mood & Wellness Data (Premium)

Premium subscribers can optionally log their mood (Tired, Meh, Glowing, or Energised) alongside their hydration percentage at that moment. This data stays on your device and is never shared with third parties.

Cycle Phase Data (Premium)

Premium subscribers may choose to enable cycle-aware hydration goals. If you do, we store the following information locally on your device:

• —Current cycle phase: self-reported (menstrual, follicular, ovulatory, or luteal), or automatically derived from your period start date.
• —Period start date: optionally provided so the app can automatically advance your phase day-by-day without requiring manual updates.
• —Cycle length preference: an integer between 21 and 40 days (default 28) used to calibrate automatic phase detection for your individual cycle.

All cycle data is stored exclusively on your device and is never transmitted to our servers, the AI coaching API, or any third party. Cycle tracking requires explicit consent, which you can provide or withdraw at any time from Settings › Cycle Tracking. Withdrawing consent and tapping "Clear" removes all stored cycle data immediately.

Glow Journey Photos

The Glow Journey feature lets you capture milestone selfies at hydration milestones (days 1, 7, 14, 30, 60, 90). Photos are stored as JPEG files inside the app's sandboxed storage on your device and are never uploaded to our servers. Metadata (milestone day, optional note, hydration percentage) is stored locally alongside the photo.

Device & Usage Preferences

We store app preferences locally on your device: streak data, lifetime hydration score, achievements, selected theme, notification settings, leaderboard opt-in status, and subscription status. This data does not leave your device except via your private iCloud sync (see below).

Apple HealthKit Data

With your permission, we read the following data from Apple Health: active energy burned, step count, exercise minutes, and water intake logged by other apps. We use this to adjust your daily hydration goal based on your activity level. We also write your water logs back to Apple Health as dietary water samples. HealthKit data is never sent to our servers or any third-party service.

2. How We Use Your Information

• —Calculate and personalise your daily hydration goal
• —Generate personalised AI coaching messages and daily recaps
• —Track streaks, achievements, and hydration progress over time
• —Schedule smart hydration reminders based on your patterns and preferences
• —Enable social features (leaderboard, Bestie Challenges) that you explicitly opt into
• —Sync your data across your own devices via your private iCloud account

We do not use your data for advertising, profiling, or any purpose beyond operating and improving the Hydrate app and website.

3. Third-Party Services

OpenRouter / Google Gemini AI

To generate personalised coaching messages, we send a limited set of data to the OpenRouter API, which routes requests to Google's Gemini AI model. This includes your first name, current hydration percentage, streak count, time of day, AI coaching mode, and aggregated hydration patterns (e.g. weekly averages). No persistent account is created with OpenRouter or Google on your behalf. Messages are cached on-device to minimise API requests. Responses are not used to train AI models.

Apple CloudKit

We use Apple CloudKit in two ways:

• —Private iCloud sync: Your profile, water logs, mood entries, and app preferences are automatically synced to your private iCloud account using Apple's encrypted infrastructure. Only you can access this data.
• —Public CloudKit database: If you choose to join the Weekly Leaderboard or a Bestie Challenge, limited data (your first name, hydration score, streak, average hydration percentage) is stored in a public CloudKit database and visible to other participants. Leaderboard participation is always opt-in. You can opt out at any time in Settings.

Apple HealthKit

HealthKit integration is subject to Apple's own privacy framework. Data exchanged with HealthKit remains under your control and is governed by your iOS Health settings. We only access HealthKit data you explicitly authorise.

Google Analytics (Website Only)

We use Google Analytics 4 on hydrateai.app to understand how visitors use the website (pages viewed, clicks, general location by country). This is website-only — the iOS app does not use Google Analytics or any third-party analytics SDK. GA4 data is governed by Google's privacy policy.

4. Referral Programme

Each user receives a unique referral code. When someone installs the app using your referral link, a record is created in our CloudKit database linking the two install codes (not names or personal details). This is used to credit referrals on the leaderboard and unlock in-app rewards. No personal data beyond install codes is stored in referral records.

5. Data Storage & Security

• —All personal data is stored primarily on your device, protected by iOS's built-in data protection.
• —iCloud sync uses Apple's end-to-end encryption infrastructure.
• —Glow Journey photos are stored in the app's sandboxed directory and are not accessible to other apps.
• —We do not operate our own servers or databases storing your personal data.
• —API keys used to access third-party services are not stored in the app bundle.

6. Data Sharing

We do not sell, rent, or trade your personal information. We share data only as described in this policy:

• —With OpenRouter/Google Gemini AI to generate coaching messages (limited, as described above)
• —With Apple via CloudKit for iCloud sync and social features you opt into
• —With other Bestie Challenge participants — only your first name and hydration progress
• —With leaderboard participants — only your first name and weekly score (opt-in only)
• —As required by law, legal process, or to protect the safety of users or others

7. Your Rights & Controls

You have meaningful control over your data:

• —Delete your data: You can delete your profile and all associated data from the Settings screen inside the app. Uninstalling the app removes all locally stored data.
• —HealthKit access: Revoke at any time in iOS Settings › Health › Data Access & Devices.
• —Notifications: Disable in iOS Settings › Notifications › Hydrate, or within the app's Settings screen.
• —Leaderboard: Opt out at any time in Settings. Your public leaderboard record will be removed.
• —iCloud sync: Manage in iOS Settings › Apple ID › iCloud.
• —Website analytics: You can opt out of Google Analytics via a browser extension or by enabling Do Not Track in your browser settings.

8. Data Retention

Your data is retained on-device for as long as you use the app. iCloud data is retained according to Apple's iCloud policies. Public leaderboard and Bestie Challenge records in CloudKit are retained for the duration of the relevant week or challenge, after which they are eligible for deletion. If you delete the app, all local data is removed. To request deletion of any CloudKit records associated with your account, contact us at the email below.

9. Children's Privacy

Hydrate is not directed at children under the age of 13 (or the applicable minimum age in your jurisdiction). We do not knowingly collect personal information from children. If you believe a child has provided us with personal information, please contact us and we will take steps to delete it.

10. Changes to This Policy

We may update this Privacy Policy from time to time. When we do, we will update the "Last updated" date at the top of this page. For significant changes, we will notify you via an in-app notice. Your continued use of the app after changes are posted constitutes your acceptance of the updated policy.

11. Contact Us

If you have any questions or concerns about this Privacy Policy or how we handle your data, please reach out: