TreadCal Privacy Policy

Last updated September 20, 2026

TreadCal is an iPhone and Apple Watch app for recording incline-treadmill workouts. It is designed to work without an account, advertising, analytics, or a developer-operated server.

Data TreadCal uses

With your permission, TreadCal can read or write the following data through Apple Health and device sensors:

• Body weight, when you choose to import it for calorie calculations.
• Heart rate during an active Apple Watch workout.
• Workouts and Active Energy so a completed TreadCal workout can appear in Health and Fitness and be restored in the TreadCal companion app.
• Motion and step data for treadmill incline calibration and completed-workout step counts.
• Workout settings and results, including speed, incline, duration, estimated calories, vertical gain, weighted-vest load, and rail-use selection.

How data is handled

TreadCal processes workout and profile data on your iPhone and Apple Watch. The paired devices exchange settings, access status, and workout receipts using Apple's WatchConnectivity framework. TreadCal does not send this data to the developer or to a third-party server.

TreadCal does not sell personal data, use it for advertising, or use Health data for marketing or data mining.

Storage and retention

TreadCal stores profile settings, treadmill calibrations, recent workout receipts, App Store purchase entitlement, and pending paired-device transfers in the app sandboxes on your devices. Completed workouts and Active Energy can also be stored in Apple Health when you grant permission. Apple processes purchases under its own terms; TreadCal receives only the verified entitlement needed to unlock the app.

You can remove local TreadCal data by deleting the app. You can review or delete Health data and change TreadCal's Health permissions in Apple's Health app. Data already saved in Health is managed by Apple Health and your iCloud settings.

Your choices

Health and Motion access is optional. You can decline or revoke permissions in iPhone Settings or the Health app. Some features, such as heart rate, steps, Health workout saving, Fitness contribution, or Health history recovery, will not work without their related permission.

Website and support email

This website does not add advertising trackers or analytics. Our hosting provider may process technical request data, such as IP addresses and browser information, to deliver and secure the website. If you email support, Carbide Studios and its email provider process your email address and message to respond. Please do not send health records. We retain support correspondence only as needed to resolve requests and meet applicable obligations; you can contact us to request deletion.

Changes to this policy

If TreadCal's data practices change, this policy and the App Store privacy disclosures will be updated before the changed version is distributed.

Contact

For privacy questions, email treadcal@carbidestudios.ai.