Privacy Policy

Last updated: March 2026

1. Overview

Dossi is an open-source, DIY automated insulin delivery system. This privacy policy explains how Dossi handles your health data.

2. What Data Dossi Collects

Dossi collects the following health data to function as an automated insulin delivery system:

• Glucose data: Continuous glucose readings from your CGM (Dexcom, Freestyle Libre, or HealthKit)
• Insulin data: Boluses and basal rates delivered by your Omnipod
• Contextual health data: Sleep duration, exercise activity, heart rate, stress (via HRV), and optional menstrual cycle data
• Meal logs: Carbohydrates and macronutrients you enter for meals
• Dosing logs: Every insulin calculation and the reasoning behind it
• Settings: Your insulin pump parameters, safety limits, and learning preferences

3. Where Your Data Stays

By default, all your data stays on your iPhone. Dossi uses Apple's SwiftData framework to store everything locally. Your glucose, insulin, and health information never leave your device unless you explicitly authorize it.

4. Cloud Sync (Optional)

Dossi offers optional cloud sync via Supabase for:

• Backing up your data
• Syncing between your devices (iPhone, iPad)
• Sharing read-only glucose views with caregivers

Cloud sync is entirely optional. If you don't enable it, no data leaves your device. If you do enable it:

• Your data is encrypted in transit
• You control what gets synced
• You can delete synced data anytime

5. Authentication

If you use Supabase cloud sync, Dossi requires authentication (email/password or OAuth):

• Authentication is encrypted and managed by Supabase
• Dossi doesn't see your password
• You can delete your account and all synced data anytime

6. HealthKit Integration

Dossi integrates with Apple HealthKit to read:

• Sleep duration and quality
• Workout/exercise data
• Heart rate and HRV
• Glucose readings (if available from your CGM)
• Menstrual cycle information (optional)

Dossi requests explicit permission for each HealthKit data type. You control what Dossi can read. All HealthKit data stays on your device.

7. Learning & Personalization

Dossi learns your personal insulin sensitivity and patterns by analyzing your glucose outcomes. This learning:

• Happens entirely on your device
• Uses Bayesian statistical inference
• Can be disabled anytime (Calibration Mode)
• Is bounded to prevent dangerous drift

8. Audit Logging

Dossi maintains an immutable audit log of:

• Every insulin recommendation and delivery
• The reasoning behind each decision (which factors were considered)
• Every safety validation check
• Manual boluses and settings changes

This log is for your review and documentation. It never leaves your device unless you export it manually.

9. Data Sharing & Third Parties

Dossi will never sell, rent, or trade your health data. Ever.

The only way your data is shared:

• You authorize it: You can share read-only glucose views with caregivers via Supabase (still encrypted)
• You export it: You can export your data as CSV for sharing with healthcare providers
• Code review: Open-source code means anyone can audit what Dossi does with data

10. Data Retention

You control your data retention:

• All local data stays on your device until you delete it
• You can delete glucose readings, insulin logs, and settings anytime
• If you use cloud sync, you can delete synced data anytime
• If you delete your Supabase account, all synced data is deleted

11. Security

Local storage: Your iPhone's built-in encryption protects local data (Secure Enclave).

Cloud storage: Supabase uses industry-standard encryption in transit (TLS) and at rest.

Authentication: Passwords are hashed. Dossi uses biometric authentication (Face ID/Touch ID) for insulin delivery.

Open source: Because Dossi is open-source, anyone can audit the code to verify security practices.

12. Regulatory Status

Dossi is not FDA approved or cleared. It is open-source software created by the community. Users are responsible for:

• Understanding how Dossi works
• Reviewing the algorithm and safety features
• Making informed decisions about their diabetes management
• Consulting with healthcare providers about use

13. Your Rights

You have the right to:

• Access: View all your health data stored in Dossi anytime
• Export: Export your data as CSV or JSON
• Delete: Delete any data, anytime
• Opt-out: Disable cloud sync, learning, or specific HealthKit permissions
• Audit: Review the open-source code to see exactly what Dossi does

14. Changes to This Policy

Dossi may update this privacy policy as features or practices change. Changes will be posted here with a new "last updated" date. Your continued use of Dossi after changes constitutes acceptance of the updated policy.

15. Contact

Questions about your privacy or this policy? Contact us at team@hellodossi.com.