Privacy Policy

Effective date: March 19, 2026

MigraineLog is designed with privacy at its core. All your health data is stored locally on your device. We have no accounts, no cloud storage, and no way to access your personal information.

1. Who We Are

MigraineLog is developed and maintained by an independent developer ("we", "us", "our"). The app is available on the Apple App Store (App ID: 6759878642). If you have questions about this policy, contact us at support@migrainelog.app.

2. Data We Collect

2.1 Data Stored On Your Device

All migraine logs, health data, preferences, and personal information you enter into MigraineLog are stored exclusively on your device using Apple's SwiftData framework. This includes:

Migraine attack records (dates, intensity, duration, triggers, symptoms)
Medication and caffeine logs
Weather and barometric pressure readings
Clinical assessment scores (MIDAS, HIT-6)
Your name and preferences

We never upload, sync, or transmit this data to any server. We have no ability to view, access, or recover your data.

2.2 Data Shared with Third-Party Services

MigraineLog uses a small number of third-party services for app functionality. None of these services receive your personal health data:

Service	Purpose	Data Sent
TelemetryDeck	Privacy-focused analytics	Anonymous usage signals (no personally identifiable information). See TelemetryDeck Privacy.
Sentry	Crash reporting	Crash logs and device metadata (no personally identifiable information). See Sentry Privacy.
RevenueCat	Subscription management	Anonymous user IDs and purchase receipts. See RevenueCat Privacy.
Apple WeatherKit	Weather data for migraine correlations	Device location (handled entirely by Apple). See Apple Privacy.

3. Apple HealthKit

MigraineLog can optionally read data from Apple HealthKit with your explicit permission. HealthKit integration is read-only. Health data accessed through HealthKit:

Is never sent to any server, including ours
Is never used for advertising or marketing
Is never sold or shared with third parties
Remains on your device at all times

You can revoke HealthKit access at any time in iOS Settings > Privacy & Security > Health.

4. Location Data

MigraineLog requests location access solely to provide weather and barometric pressure data relevant to migraine tracking. Your location is:

Sent only to Apple WeatherKit to retrieve weather forecasts
Stored locally on your device alongside weather readings for historical comparison
Never sent to our servers (we have none) or any third party other than Apple

You can disable location access at any time in iOS Settings > Privacy & Security > Location Services.

5. On-Device AI

MigraineLog's AI Insights feature processes your migraine data entirely on your device using Apple Foundation Models. No data leaves your device for AI processing. On devices that do not support on-device AI, a rule-based analysis engine is used instead.

6. Advertising and Tracking

MigraineLog contains:

No advertisements of any kind
No ad tracking or ad identifiers
No cookies (it is a native iOS app)
No data selling or sharing for marketing purposes

7. Subscriptions

MigraineLog offers optional premium subscriptions managed entirely through Apple's App Store:

Weekly: $1.99 USD
Monthly: $4.99 USD
Annual: $29.99 USD

Payment processing is handled by Apple. We receive anonymous transaction data through RevenueCat to manage subscription status. We never see your payment details, Apple ID, or billing information.

8. Data Retention and Deletion

Since all data is stored on your device:

Your data persists as long as the app is installed
You can delete all data at any time from within the app (Settings > Delete All Data)
Uninstalling the app removes all locally stored data
We retain no copies because we never had access to your data

9. Children's Privacy

MigraineLog is not directed at children under 13. We do not knowingly collect information from children. Since all data is stored locally and we have no accounts or registration, we have no way to identify or contact users of any age.

10. International Users

MigraineLog is available in 10 languages (English, Spanish, German, French, Portuguese, Japanese, Korean, Simplified Chinese, Italian, and Dutch). Because your data stays on your device, there are no cross-border data transfers to be concerned with. The third-party services listed in Section 2.2 may process their limited anonymous data in accordance with their own privacy policies.

11. Your Rights

Regardless of your jurisdiction (GDPR, CCPA, or other privacy regulations):

Access: All your data is visible to you within the app at all times
Portability: You can export PDF reports of your data from within the app
Deletion: You can delete all data from Settings > Delete All Data
There is nothing to request from us because we do not hold any of your personal data

12. Security

Your data is protected by your device's built-in security features, including device passcode, Face ID/Touch ID, and Apple's hardware encryption. Since data never leaves your device, there is no server-side attack surface.

13. Changes to This Policy

We may update this privacy policy from time to time. Changes will be posted on this page with an updated effective date. Continued use of MigraineLog after changes constitutes acceptance of the revised policy.

Contact

If you have any questions about this privacy policy or MigraineLog's data practices, please contact us at support@migrainelog.app.