Don’t believe it? I too didn’t until I read about this PressureNET open-source android app recently. This is a crowd-sourced app and its working is simple: Just gauge these two parameters:
1) Atmospheric pressure using the pressure sensors (available in latest android phones like Galaxy S4/Nexus), and
2) GPS coordinates using the GPS sensor.
and send the data to the PressureNET web-server through Internet. Now, with enough number of people running this app on their devices, weather scientists across the nation have access to substantial data regarding pressure-belts forming in various parts of the country. They can then input this data to their weather modeling systems and come-up with solid predictions! (not just vague guesses like now) regarding for example, when and exactly where the next hurricane is going to hit. According to Cliff Mass, an atmospheric Scientist at the University of Washington, this data can help predict an occurrence of a hurricane up to six hours earlier. There is currently, no technique to do it now.
Whilst the pressure-sensor is being used for this purpose, the intentions of Google was something totally different when putting this feature into the android OS. It was to fetch the altitude information. You see, the GPS tells you only the Geo-coordinates (Lat/Lon) on a plane surface. But the atmospheric-pressure changes as a person travels uphill or downwards, and thus it can let us know exactly what altitude a person is on!