Cortex — Privacy Policy
Last updated: September 6, 2026
Cortex ("the app") is a personal attention lab. The short version: your data lives on your iPhone, there is no account, and we do not track you or sell anything about you.
What stays on your device
- Your test data: reaction-test sessions, daily scores, streaks, experiments, verdicts, and check-ins are stored in a local database on your iPhone. They are never uploaded. There is no account and no cloud sync.
- Apple Health (optional): if you grant access, Cortex reads four things, read-only: sleep, heart-rate variability (SDNN), resting heart rate and step count. They are used for three purposes only: to show context beside the day's score, to compute the Pro "correlations" hints (for example score vs sleep), and to flag a sleep change that could confound an experiment. Each morning's values are stored in the app's local database on your device, are processed on the device, and are never transmitted to us or anyone else. The only way they can leave your phone is inside a CSV export that you create and share yourself. Cortex never writes anything to Health. You can revoke access at any time in the Health app (Sharing → Apps → Cortex).
What we do not do
We do not sell your data. We do not show ads. We do not use analytics or cross-app tracking SDKs — the app shows no tracking prompt because it does not track you. We do not collect your location, contacts, or identity.
Subscriptions and payments
Purchases are processed by Apple. We never see or store your payment details.
Third parties
Cortex uses one third-party service, RevenueCat, to check whether a Cortex Pro purchase is active and to restore it after a reinstall. RevenueCat receives an anonymous, app-generated identifier, your purchase and entitlement state, and the standard metadata of any internet request: IP address, device model, operating system version, app version and locale. It receives no Health data, no test results and nothing that identifies you by name or email. RevenueCat keeps this purchase record for as long as it is needed to restore your purchase; its own policy is at revenuecat.com/privacy. No other SDK, analytics service or server is involved.
Exporting and deleting your data
You can export your history as CSV from Settings at any time (the last 30 days on the free plan, your full history with Pro; Health values Cortex read are included). Deleting the app deletes all data stored on your device, because that is the only place it lives; Settings also offers a full in-app erase. The anonymous purchase record at RevenueCat is not on your device — email us and we will have it deleted.
Backups
Like any app, Cortex's local database is included in your iPhone backup (iCloud or computer). Apple's backup protections apply; we have no access to it.
Contact
Questions about this policy: platelogic26@gmail.com