California is earthquake country. It's estimated there's a quake in the state every three minutes, although most are too small to be noticeable.
It's a danger we live with every day.
While scientists can't predict earthquakes, seismologists are using smartphones to give us a warning that shaking has started - enough time to seek shelter. But cellphone technology does not stop there.
Google engineers are using motion sensors built into Android phones to detect earthquakes as well. All it takes is a few seconds to set up your smartphone to be ready for the next big one.
Want to explore how earthquakes have affected California? See our maps below:
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