The University of California, Irvine, has launched smartphone app iRain, which aims to put precision rainfall information into the pockets of the public. The free app, which is available for iPhone and Android devices, will use satellite rain data from the universitys weather tracking and analysis system. iRain users will also be able to enter their own rain or snowfall observations, joining what the University of California, Irvine (UCI) calls a globe-spanning cadre of citizen hydrologists. The beauty of iRain is that its an access point for an entire system that detects, tracks and studies precipitation on our planet, said lead developer Phu Nguyen, assistant adjunct professor of civil and environmental engineering. We process the data from satellites and offer it to the end user, free of charge. As far as I know, were the only institution offering such a system. Features include a tool that displays the top 50 current extreme weather events around the world, animations that show varying levels of rainfall intensity and movement, a function to choose different time spans and a tool to zoom in to a local area. Many of iRains functions have also been made available online, enabling researchers to generate and download reports. UCI uses data from US, European and Japanese satellites, in collaboration with agencies such as NASA and NOAA, to produce rainfall information that is accessed by people in more than 180 countries.