Privacy Policy

1. Core Architectural Principle: 100% On-Device

Runalyst was engineered under a strict zero-knowledge, zero-cloud architecture. We believe your physiological and running biometric data belongs entirely to you. Runalyst operates with no accounts, no logins, no tracking pixels, and no remote servers. All computation, mathematical analysis, and coaching inference takes place directly on your iPhone and Apple Watch.

2. Apple HealthKit Data Collection & Use

With your explicit permission via iOS system prompts, Runalyst accesses Apple HealthKit strictly to analyze running workouts and calculate biomechanical progression. Specifically, Runalyst accesses:

• Workout Samples: Running distance, duration, energy burned, and timestamps.
• Biomechanical Telemetry: Running Cadence (SPM), Vertical Oscillation (cm), Ground Contact Time (ms), and Stride Length (m).
• Cardiorespiratory Metrics: Heart Rate time-series and VO2 Max estimates.

HealthKit Data Restrictions: Under no circumstances will Runalyst disclose, sell, transmit, or share your HealthKit data with third-party advertisers, data brokers, or external analytics platforms. HealthKit data is used exclusively to display running metrics and generate personalized on-device coaching.

3. On-Device Foundation Models & AI Processing

AI coaching observations and drill prescriptions are generated locally on your iPhone using Apple Silicon FoundationModels. Your workout statistics and telemetry are never uploaded to OpenAI, Anthropic, or any cloud API. The coaching loop functions completely offline without an active internet connection.

4. Local Storage with SwiftData

Runalyst persists your cached metrics and drill completion states in a private on-device SQLite database managed by Apple SwiftData. Your data is protected by iOS hardware-level Data Protection and encryption while your device is locked.

5. User Control & Data Deletion

You retain absolute sovereignty over your data. In the Runalyst Settings tab, tapping "Resync Health Data & Rebuild AI Insights" immediately purges all local SwiftData caches. If you delete the app from your device, all local Runalyst data is permanently removed. You can modify or revoke HealthKit permissions at any time via iOS Settings > Privacy & Security > Health > Runalyst.

6. Contact & Inquiries

If you have questions regarding this Privacy Policy or Runalyst's technical architecture, please reach out via our App Store listing at App Store: Runalyst.