Your privacy is important to us
Last Updated: November 20, 2025
Scientific Altimeter does not collect, store, or share any personal data. The app is designed with privacy as a core principle. All altitude measurements, location data, and sensor readings stay on your device. No analytics, no tracking, no third-party services.
Scientific Altimeter does not collect any of the following:
The app requires access to your device's location for two specific purposes:
Your device's GPS receiver provides real-time altitude based on satellite positioning. This data is displayed to you in real-time and is never stored or transmitted anywhere.
When you use the calibration feature, the app sends your current GPS coordinates to the USGS National Map Elevation Point Query Service (EPQS) to retrieve ground elevation data at that location. This query contains only latitude and longitude coordinates and no identifying information about you or your device.
Important: Location data is used only for real-time measurement and calibration. It is never stored on your device (beyond iOS system caching), never transmitted to us, and never shared with any third parties except USGS for calibration.
The app includes an optional data logging feature that allows you to record altitude measurements for later analysis. This data is stored locally on your device only. You control when to log data, when to export it, and when to delete it. Logged data never leaves your device unless you explicitly export it.
Scientific Altimeter uses only one third-party service:
When you use the calibration feature, the app queries the USGS National Map EPQS API to obtain ground elevation data. This query contains only geographic coordinates (latitude and longitude) and no personally identifiable information.
The USGS is a U.S. government scientific agency. Their API is a free, public service. Learn more about USGS data services at usgs.gov/privacy-policies.
The app requests the following iOS permissions:
Required to access GPS altitude and coordinates for measurement and calibration. You can choose "While Using App" or "Always" permission level. The app only accesses location when in use.
What happens if you deny location permission: The app cannot function without location access, as its core purpose is to measure altitude based on your location.
All data generated by Scientific Altimeter (logged measurements, calibration settings, app preferences) is stored locally on your device using iOS standard storage mechanisms. This data is:
Scientific Altimeter does not collect any data from anyone, including children under 13. The app is appropriate for educational use by students of all ages under teacher supervision. No account creation or personal information is required.
We may update this privacy policy from time to time to reflect changes in the app or legal requirements. Any changes will be posted on this page with an updated "Last Updated" date. Continued use of the app after changes constitutes acceptance of the updated policy.
Since we do not collect any personal data, there is no user data for us to access, modify, or delete. You have complete control over any data stored locally on your device:
If you have questions about this privacy policy or the app's privacy practices, please contact us:
Email: [email protected]
Developer: Mark
GIS/Watershed Specialist
UNC Chapel Hill
This privacy policy is designed to comply with:
We built Scientific Altimeter with privacy as a fundamental principle, not an afterthought. We don't want your data. We don't need your data. We don't collect your data. Your measurements are yours alone.