Atmotube PRO has barometer and altimeter functions. The device reports atmospheric pressure and altitude in real time.
Altimeter
The default altitude value is set by the GPS data (if GPS is enabled in the settings).
p0 - calculated mean sea level pressure
p - measured/barometric pressure
h - elevation of measured data
T - measured air temperature
Altitude is also calculated based on the difference between current atmospheric pressure and pressure at mean sea level. Every 8.8 meters, atmospheric pressure drops by 1 mbar.
Pressure at mean sea level is received from the weather server based on GPS location. This value can also be entered manually.