How Did an App Know an Earthquake Was Hitting California Before It Happened?

Quake Alert
The Quake Alert app warns users before an earthquake is about to hit.
(Image credit: Early Warning Labs; Getty)

Some people in Los Angeles knew about today's earthquake before it even hit.

Those who had the beta Quake Alert application on their smartphones got about a 30-second warning before the shaking hit at 12:29 p.m. PDT (19:29 UTC). The magnitude-5.3 earthquake struck about 38 miles (61 kilometers) off the coast of California today (April 5), according to the U.S. Geological Survey (USGS).

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Laura Geggel
Managing Editor

Laura is the managing editor at Live Science. She also runs the archaeology section and the Life's Little Mysteries series. Her work has appeared in The New York Times, Scholastic, Popular Science and Spectrum, a site on autism research. She has won multiple awards from the Society of Professional Journalists and the Washington Newspaper Publishers Association for her reporting at a weekly newspaper near Seattle. Laura holds a bachelor's degree in English literature and psychology from Washington University in St. Louis and a master's degree in science writing from NYU.