MIT Technology Review recently reported on a new app called Sunshine that uses crowdsourcing to create more accurate, localized weather forecasts. The app, currently in a private beta test, combines data from the National Oceanic and Atmospheric Administration (NOAA) with atmospheric pressure readings captured by a smartphone. The latest iPhones, and some Android smartphones, include barometers for measuring atmospheric pressure. While these sensors are usually used to determine elevation for navigation, changes in air pressure can also signal changes in the weather. Sunshine will also rely on users to report sudden weather hazards like fog. About 250 people spread out among the Bay Area, New York, and Dallas are currently using Sunshine.

You can read more about this at MIT Technology Review.