ShakeAlertLA, an app commissioned by the city of L.A. for use in the entire county of Los Angeles, can now be downloaded — for free! — to Android and Apple devices. A network of ground sensors, operated by the U.S. Geological Survey, detects the earliest indications of shaking. The app then sends an immediate message that an earthquake is on the way and the kind of shaking to be expected (light, moderate, or severe). It might not be perfect — there could be false alarms, or, conversely, failures to detect a quake. But the technology has been used, mostly successfully, in other countries and should work here as well. It is the first such warning system in the United States and a tool to help us deal with the inevitable big one.
Source: latimes.com – Los Angeles Times