Privacy Policy

1. Introduction

My Diabetes Friend ("we," "our," or "the Service") is committed to protecting your privacy. This Privacy Policy explains how we collect, use, disclose, and safeguard your information when you use our application.

We process your data in accordance with the EU General Data Protection Regulation (GDPR), the California Consumer Privacy Act (CCPA), and other applicable privacy laws. While My Diabetes Friend is not a HIPAA-covered entity, we follow HIPAA-aligned safeguards for all health data we handle.

2. Who We Are

For GDPR purposes, the data controller is:

Company: [YOUR COMPANY NAME]
Address: [YOUR COMPANY ADDRESS]
Email: privacy@mydiabetesfriend.app
Registration: [COMPANY REGISTRATION NUMBER]

Fill in company details once your legal entity is established. The company location determines which data protection authority has primary jurisdiction.

3. Information We Collect

3.1 Information You Provide

• Account Information: Email address, name, password (encrypted)
• Profile Settings: Glucose target ranges, preferences, timezone
• Menstrual Cycle Data: If you choose to enable cycle tracking

3.2 Health Data (Special Category Data)

We collect health-related data that you choose to share with us:

• Glucose readings from connected CGM devices (Dexcom, via Nightscout, Tidepool, LibreLinkUp)
• Sleep and recovery data from connected wearables (WHOOP, Oura Ring)
• Menstrual cycle data (optional, for cycle tracking features)
• Heart rate variability (HRV) and resting heart rate
• Patterns and insights generated from your health data
• Meal information (Friend Plus subscribers only, optional): a label, macro estimates (carbohydrates, protein, fat in grams), and the time you ate. If you use the photo-meal feature, the photo is sent to our AI vision provider (Anthropic) for macro estimation. We do not save the image on our servers; Anthropic's policies apply to what they receive — see § 5.3 below.

3.3 Technical Data

• Usage Data: Features used, pages visited, time spent
• Device Information: Browser type, operating system
• Cookies: Session cookies for authentication

3.4 Third-Party Device Data

When you connect third-party services, we receive:

• Dexcom: Glucose readings, trend data
• WHOOP: Sleep stages, recovery scores, strain, HRV
• Oura: Sleep data, readiness scores, activity data
• Tidepool / Nightscout: Historical and real-time glucose data
• FreeStyle Libre: Glucose readings via LibreLinkUp

4. Why We Process Your Data

4.1 To Provide the Service

• Display your glucose readings and trends
• Analyze patterns in your health data
• Generate personalized insights
• Sync data from connected devices

4.2 With Your Explicit Consent (Health Data)

For processing your health data, we rely on your explicit consent under GDPR Article 9(2)(a). You provide this consent when creating an account, connecting a health device, or enabling specific features (e.g., cycle tracking).

5. How We Protect Your Data

5.1 Security Measures

• Encryption in transit (HTTPS/TLS) and at rest (AES-256)
• Access controls and secure authentication (passwords hashed with bcrypt)
• Infrastructure hosted on Vercel and Neon PostgreSQL

5.2 Data Minimization

We only collect data necessary to provide the Service. We do not sell your data to third parties or share your health data with advertisers.

5.3 AI Safety

Our AI Friend feature:

• Never provides medical advice
• Is designed with safety filters to prevent harmful responses
• Stores your Friend chat messages on our servers until you delete your account, so the feature can remember your conversations
• Sends conversation content to Anthropic to generate replies, including the name you asked to be called; Anthropic's policies apply to what they receive

Photo-meal feature (Friend Plus subscribers only):

• Sends your meal photo to our AI vision provider (Anthropic) to estimate macros (carbs, protein, fat)
• Does not save the photo on our servers — after macro estimation, we keep only the numbers and label you confirm
• Persists only the macro numbers and meal label you confirm — never the image bytes themselves

6. Who We Share Data With

6.1 Service Providers

We share data with providers who help us operate the Service:

• Vercel — Hosting, database (encrypted)
• Stripe — Payment processing (email, payment details)
• Resend — Email delivery
• Anthropic — AI Friend chat and photo-meal macro estimation (message content, including your chosen name when your account has one; your email address and account ID are not sent; meal photos when you use that feature — Anthropic's policies apply)
• Sentry — Error monitoring (crash and error reports; Sentry's policies apply)
• PostHog — Product analytics on the web when you opt in (PostHog's policies apply)

6.2 Community Benchmark Insights (Optional)

Community Benchmark Insights is an optional feature that helps you compare your trends with similar users. This feature is off by default and only activates when you explicitly enable it in Settings.

• How it works: We compute anonymized and aggregated cohort metrics (for example, time-in-range averages).
• No direct sharing: Other users cannot see your identity or your individual records.
• Minimum cohort threshold: We only show benchmark comparisons when enough users are present in a cohort.
• Control: You can disable this feature at any time in Settings.

5.2 Dexcom Data Handling

We access your Dexcom data exclusively through the official Dexcom Developer API using OAuth 2.0 authorisation.

• We request only the data scopes necessary: estimated glucose values (egv) and refresh tokens (offline_access).
• Access and refresh tokens are stored in encrypted, httpOnly cookies — never in client-side storage.
• Glucose data retrieved from Dexcom is used solely to display trends, generate pattern insights, and power the AI companion features within this app.
• We do not re-distribute, re-sell, or share raw Dexcom data with any third party.
• You can revoke access at any time from Settings or directly from your Dexcom account.

6. Data Retention

We retain your data for as long as your account is active or as needed to provide the Service.

• Health Data: Retained while your account is active; deleted within 30 days of account deletion
• Account Data: Deleted upon account deletion request
• Payment Records: Retained for 7 years for tax/legal purposes

7. Data Security

We protect your data using:

• TLS/SSL encryption for all data transmission
• Encrypted database storage
• OAuth 2.0 for third-party authentication
• HTTP-only secure cookies for session management
• Password hashing using bcrypt
• Regular security audits

8. Your Rights

8.1 For All Users

• Access: View your data in the app or request a copy
• Correction: Update your information in Settings
• Deletion: Delete your account and all associated data
• Disconnect: Revoke device connections at any time

8.2 Additional Rights for EU Residents (GDPR)

• Data Portability: Receive your data in a machine-readable format
• Restriction: Request restriction of processing
• Object: Object to processing based on legitimate interests
• Withdraw Consent: Withdraw consent at any time
• Lodge Complaint: File a complaint with your supervisory authority

8.3 Additional Rights for California Residents (CCPA)

• Know: Request disclosure of data collected and shared
• Delete: Request deletion of your personal information
• Opt-Out: We do not sell personal information
• Non-Discrimination: Exercise rights without discriminatory treatment

To exercise your rights, contact us at privacy@mydiabetesfriend.app or use the account settings in the app.

9. Cookies & Tracking

We use:

• Essential Cookies: Required for authentication and security (cannot be disabled)
• Analytics Cookies: Help us understand usage patterns (can be disabled)

You can manage cookie preferences through your browser settings or our cookie consent banner.

10. International Data Transfers

Your data may be processed in countries outside your residence. For transfers from the EU/EEA, we use:

• Standard Contractual Clauses approved by the European Commission
• Data processing agreements with all service providers

11. Children's Privacy

The Service is not intended for children under 13. We do not knowingly collect data from children under 13. Users aged 13-17 require parental consent.

12. Data Breach Notification

In the event of a personal data breach that is likely to result in a risk to your rights and freedoms, we will notify affected users without undue delay and, where required under GDPR, inform the relevant supervisory authority within 72 hours of becoming aware of the breach.

13. Changes to This Policy

We may update this Privacy Policy periodically. We will notify you of material changes via email or in-app notification at least 30 days before they take effect.

14. Contact Us

For privacy-related questions or to exercise your rights:

Data Protection Officer
Email: privacy@mydiabetesfriend.app
Address: Denmark, European Union

We aim to respond to all requests within 30 days.