Privacy Policy — SignalVeil
Last updated: August 11, 2026
1. Overview
SignalVeil ("we", "us") respects and protects your privacy. This Privacy Policy explains how we collect, use, store and disclose your information when you use the SignalVeil iOS application (the "App").
By using the App, you agree to the terms of this Privacy Policy.
2. Information We Collect
2.1 Health Data (HealthKit)
The App accesses read-only access to 8 core metrics in Apple Health (HealthKit):
- Sleep Duration
- Resting Heart Rate
- Heart Rate Variability
- Respiratory Rate
- Active Energy
- Step Count
- Body Weight
- Blood Oxygen
This health data is stored only on your device and is used for on-device trend analysis. We do not upload raw health data to any server.
2.2 Information You Provide
- Feeling check-ins: the mood you select each day (good / okay / bad) and any optional note. These are stored locally on your device only.
- Questions you ask: the text of questions you enter in the "Ask" feature.
2.3 Usage Data
We collect basic anonymous usage data (such as the app version number), used only to improve product quality and compatibility analysis.
We do not collect personally identifying information such as your name, email address or phone number.
We do not collect precise location data.
We do not collect sensitive data such as your contacts, photo library or microphone.
We do not sell your data to any third party.
3. How We Use Information
We use the information we collect for the following purposes:
- On-device trend analysis: computing 7-day / 30-day trends, signal-vs-noise classification, and conflict arbitration between how you feel and what your data shows — all on your device.
- AI-generated briefs: when you use the "AI Brief" or "Ask" features, the App sends the trend summary produced by the rule engine (aggregated averages and direction of change, not raw health records), your feeling check-in state, and the question you typed to a third-party AI service provider in order to generate natural-language content.
- Improving the product: analysing anonymous usage trends to improve answer quality and product features.
- Customer support: helping to troubleshoot issues when you contact us.
4. Data Storage and Security
- Health data: stored on your device only, processed locally, never uploaded.
- Transmission security: trend summaries are sent only when you use an AI feature, and all transmission is encrypted over HTTPS.
- No account: the App does not require you to create an account, and there is no cloud storage of health data.
- Data deletion: uninstalling the App deletes all local data from your device. The AI service provider retains request data used to generate content only for its standard cache period.
5. Third-Party Services
The App uses the following third-party services:
| Service | Purpose | Data involved |
|---|
| Alibaba Cloud Model Studio (DashScope) |
AI generation of briefs and answers |
Trend summaries output by the rule engine and your question (no raw health records) |
| Apple App Store |
Subscription payment and in-app purchase |
Payment information, handled by Apple |
| RevenueCat |
Subscription status management |
Purchase / subscription status (no health data) |
6. Subscriptions and Purchases
The App's paid features (SignalVeil Pro) are offered as auto-renewable subscriptions through the Apple App Store. All payments are processed by Apple. RevenueCat receives only your subscription status in order to unlock the corresponding features, and never receives any of your health data.
7. Children's Privacy
The App is not directed to children under 13. We do not knowingly collect personal information from children.
8. Your Rights
- Right to know: to understand what data we collect about you.
- Right to delete: uninstall the App to delete local data from your device.
- Right to correct: manage or delete your health data in Apple Health.
- Right to complain: lodge a complaint with the relevant data protection authority.
9. Changes to This Policy
We may update this Privacy Policy from time to time. If we make material changes, we will notify you by an in-app notice.
10. Contact
If you have any questions about this Privacy Policy, please contact:
Email: haojia.zhang@icloud.com