Whistl Privacy Policy Explained: Your Data, Your Control

Privacy policies are notoriously confusing. Whistl's isn't. Your financial data stays on your device. We don't sell it. We don't share it. Here's exactly what happens to your data—in plain English.

Core Privacy Principles

1. Your data is yours: We never sell or share your financial data
2. On-device processing: ML training happens on your phone, not our servers
3. Minimal collection: We only collect what's necessary for features to work
4. Encryption always: AES-256-GCM encryption for all stored data
5. You control sharing: Partner sharing is opt-in with 4 privacy tiers

What Data We Collect

Financial Data (On-Device)

• Transaction history (via Plaid connection)
• Account balances
• Blocked impulse attempts
• Savings and investment data
• Storage: Encrypted on your device only

Behavioral Data (On-Device)

• Browsing patterns (VPN logs)
• App usage (Screen Time API)
• Biometric data (Oura, HealthKit)
• Mood check-ins
• Storage: Encrypted on your device only

Account Data (Encrypted Cloud)

• Email address
• Authentication tokens
• Subscription status
• Storage: Encrypted cloud storage (Firebase)

What We Do NOT Collect

• ✗ Bank login credentials (Plaid handles these)
• ✗ Full transaction details sent to our servers
• ✗ Browsing history sent to external servers
• ✗ Biometric data sent to external servers
• ✗ Data sold to third parties (ever)

How We Use Your Data

Third-Party Integrations

Plaid (Banking)

• Access: Transaction and balance data
• Purpose: Connect your bank accounts
• Data sharing: Plaid → Whistl (on-device only)

Alpaca (Investing)

• Access: Investment account
• Purpose: Execute ETF purchases
• Data sharing: Only what's required for trades

Oura/HealthKit (Biometrics)

• Access: Sleep, HRV, readiness data
• Purpose: Biometric risk prediction
• Data sharing: Never leaves your device

Your Privacy Rights

• Access: Download all your data anytime
• Deletion: Delete your account and all data
• Correction: Update inaccurate information
• Portability: Export data in standard format
• Opt-out: Disable any data collection

Security Measures

• AES-256-GCM encryption at rest
• Chain-hashed SHA-256 audit logging
• Biometric authentication for sensitive actions
• Firestore Security Rules with listener lifecycle management
• Regular security audits

Conclusion

Your financial data is sensitive. Whistl treats it that way. On-device processing. No selling. No sharing. You control everything. That's not just policy—that's promise.

Related: Privacy Policy | Security & Compliance