Privacy Policy

Effective date: September 20, 2026

Synapse ("Synapse," "we," "us") is an AI-powered health journal that lets you log food, drink, exercise, sleep, mood, symptoms, and other wellness notes, and surfaces patterns across them. This policy explains what we collect, how we use it, and the choices you have. By using Synapse you agree to this policy.

1. Information we collect

• Account: your email address and a password you choose, used to sign in. We email a one-time code at sign-up to verify your address. Passwords are stored securely (hashed) by our authentication provider; we never see them in plain text.
• Health & wellness logs: the entries you create — foods, drinks, exercise, sleep, mood, feelings, symptoms, notes, and any free text or meal photos you submit.
• Profile: optional details you provide such as age, biological sex, height, weight, activity level, goals, dietary preferences, and health context.
• Apple Health (HealthKit): if you connect it, we read data you authorize (e.g., workouts, sleep, steps, weight) to display alongside your logs. See Section 4.
• Subscription data: purchase and entitlement status from Apple / RevenueCat (we never receive your full payment card details).
• Diagnostics: basic app/usage and crash information to keep the app working.

2. How we use your information

• To provide the core service — recording your logs and showing your Today view, timeline, and trends.
• To power AI features — your messages, logged entries, and meal photos are sent to our AI provider to interpret entries, estimate nutrition, answer your questions, and generate meal-plan suggestions.
• To manage your subscription and enforce free vs. premium access.
• To send transactional email (your sign-in code) and respond to support.

3. AI processing

To interpret what you log and generate insights, relevant content (your text, entries, and meal photos) is processed by Anthropic via its API. This content is used only to generate responses for you; under Anthropic's API terms it is not used to train their models. We do not sell your data or use it for third-party advertising.

4. Apple Health (HealthKit)

Apple Health data is read only with your explicit permission and is used to display alongside your other logs and to inform the patterns and insights Synapse shows you.

Specifically: workouts and sleep you authorize are saved to your Synapse journal on our servers alongside the entries you write yourself, and — like your other entries — they form part of the recent-activity summary sent to our AI provider when you ask a question or request an analysis (see Section 3). Other metrics we read (steps, active energy, resting heart rate, weight, mindful minutes, blood glucose) are displayed in the app only and are not stored on our servers or sent to our AI provider.

We do not use HealthKit data for advertising or marketing, we do not sell it, and we do not share it with third parties for any purpose other than operating Synapse for you. You can revoke access anytime in iOS Settings → Health. Apple Health is entirely optional and is not required to use Synapse.

5. How we share information

We don't sell your personal information. We share it only with service providers that operate Synapse, under contracts that limit their use of it:

• Supabase — database, authentication, and file storage (your account and logs).
• Anthropic — AI processing of your entries/photos (Section 3).
• RevenueCat & Apple — subscription management and in-app purchases.
• Resend — delivery of your sign-in code email.
• Sentry — crash and error diagnostics (Section 1). Crash reports carry technical details about the failure and your device, not the contents of your journal entries, and are not linked to your account.

We may also disclose information if required by law or to protect rights and safety.

6. Data retention & deletion

We keep your data while your account is active. You can delete your account at any time from Settings — this removes your logs, profile, and stored photos. You may also email us to request deletion.

Settings also includes a data-retention preference. This records how long you would like your history kept; it is stored with your profile and does not yet automatically delete older entries. Until it does, your entries are kept until you delete them or delete your account.

7. Security

Data is encrypted in transit, access is restricted to your own account via row-level security, and your session is stored in the device's secure keychain. No method of transmission or storage is 100% secure, but we work to protect your information.

8. Your choices & rights

You can view and edit your logs and profile in the app, disconnect Apple Health, manage your subscription through the App Store, and delete your account. Depending on where you live, you may have additional rights (access, correction, deletion, portability) — contact us to exercise them.

9. Children

Synapse is not directed to children under 13 (or the minimum age in your country), and we do not knowingly collect their data.

10. Changes to this policy

We may update this policy; we'll revise the date above and, for material changes, notify you in the app.

11. Contact

Questions or requests: hello@synapsehealth.app  ·  Connor Vander Zalm, Seattle, WA.