100% Offline & Private

Privacy Policy — Dark Logger

Effective date: May 01, 2026

The Core Principle of Dark Logger

Dark Logger collects zero Personally Identifiable Information (PII). There are no accounts, no logins, no email requirements, and no names. Your migraine logs, symptoms, medications, and pain notes never leave your device. We do not store, view, track, or sell your health or personal data.

1. Zero Personally Identifiable Information (PII) & No Accounts

We do not know who you are, and the app is engineered specifically so we never have to:

No Account Required: You never need an email, phone number, password, or profile to use Dark Logger.
No PII Collection: We do not collect, ask for, or store names, addresses, contacts, or any identity markers.
Anonymous by Design: You interact with the app entirely anonymously.

2. Health & Attack Logs (100% On-Device)

All migraine attack entries, pain ratings, triggers, symptoms, and relief logs are stored solely in your device's secure local storage (AsyncStorage). We do not operate a centralized cloud database for your medical records, and we cannot view or access your logs under any circumstance.

3. Moving Devices & Backups (CSV Export / Import)

Because Dark Logger does not sync your medical logs to a cloud server:

Transferring to a new phone or device: To transfer your history, navigate to the History tab in Dark Logger and export your records as a CSV file. On your new device, open the History tab and use the Import CSV feature to restore your complete attack history.
Data Deletion: Uninstalling the app permanently removes your local database. Always ensure you have exported a CSV copy if you wish to keep your records outside of your standard OS-level encrypted backup (iCloud or Google Backup).

4. Location & Weather Data

To identify atmospheric triggers like barometric pressure fluctuations, Dark Logger requests location access:

When an attack is logged or pressure checks occur, your device queries public meteorological APIs (such as Met.no) using your coordinates to retrieve atmospheric pressure and temperature.
Dark Logger does not store, log, or track your location history on any server. Only the retrieved weather values (e.g. pressure, temperature) are written to your on-device attack logs.

5. Push Notifications & Non-Personal Metadata

If you opt-in to notifications (such as morning/evening check-ins or pressure drop warnings):

We securely store an anonymous Expo Push Token, device OS platform (iOS/Android), regional locale (country code), and Pro subscription status in our cloud database (Supabase).
This metadata contains no personal identifiers and is used purely to dispatch scheduled push alerts. No personal health records, names, or attack entries are ever connected to your push token.

6. Subscriptions & Attribution (RevenueCat)

We use RevenueCat to manage purchases and unlock Pro features:

RevenueCat validates anonymous receipt tokens and manages entitlement states across platforms.
On iOS, the app may collect an Apple AdServices attribution token to evaluate Apple Search Ads campaign performance without identifying you personally.
All payments are processed directly by Apple App Store or Google Play; Zeph never receives or stores payment credentials, credit card details, or billing addresses.

7. Contact Us

If you have questions about our zero-PII architecture or privacy practices, please reach out:
Email: info@zephlogic.com