Through a good algorithm that combines three different techniques, the Altimeter professional app provides precise altitude detection. Regardless of whether you have an internet connection or not, this app will show you your actual altitude. It makes use of satellite triangulation, map altitude, and, a pressure sensor calibrated with the nearby weather station. 

The app provides extremely accurate graphics together with digital measurement and an analog altimeter in meters or feet. It has a manual setup option as well as an automatic altitude measurement function. Even when the app is closed, you can still access the history feature, which records your path on a map, altitude difference graphs, and indicators of speed, average speed, and increase in altitude.