Hunter Research & Technology


Pro Altimeter uses the high-fidelity barometric pressure sensor in iOS devices to measure and compute altitude.

Pro Altimeter has a simple interface. Barometric altitude and GPS altitude are displayed in large easy to read numbers, showing units of both feet and meters, and giving realtime accuracy estimates from the hardware. At bottom are calibration and display mode buttons. The display offers a highly-readable daytime mode with black digits on an LCD-green background, and a reversed night mode that is easy on the eyes in dark conditions. That's it!

Pro Altimeter keeps track of the time since its last calibration. Because weather and local barometric pressure change over time, the app will warn you when 12 hours have elapsed since the last calibration by flashing the "CALIBRATE" button. You should calibrate as frequently as practical -- for example, on a hike, calibrate whenever you pass a trail marker or elevation benchmark. But at a minimum, calibrate at least every 12 hours or whenever weather changes in your area.

Pro Altimeter is intended for recent model iOS devices with a built-in barometric pressure sensor which include the iPhone 6/6+, iPhone 6S/6S+, iPhone 7/7+, iPad Air 2, iPad Pro, and iPad mini 4. On older devices without a barometric pressure sensor, only GPS altitude and accuracy will be displayed.

Pro Altimeter runs on iOS 8.0 or later.