Android is a massive platform with billions of active devices in use around the world. And today Google announced that it's turning them into an earthquake detection network.

The Android Earthquake Alerts System can turn your phone into a mini seismometer. It does this using the accelerometer that's built into every smartphone and is normally used for things like determining when you rotate your phone from portrait to landscape mode.

If your phone detects something that might be an earthquake, it'll send a signal to Google's earthquake detection server along with a coarse location of where the shaking happened. The server will then combine that info with lots of other phones to decide if there's an earthquake happening.

To begin with, Google is using the Android Earthquake Alerts System to give you a quick view of an area impacted by an earthquake using Google Search. Just look up "earthquake" or "earthquake near me" and you'll get the relevant info for where you live.

Google is taking things a step further in California. It's working with the United States Geological Survey and California Governor's Office of Emergency Alerts to send earthquake alerts directly to Android devices in the state.

These alerts are powered by ShakeAlert, a system made by leading seismologists that uses signals from more than 700 seismometers installed throughout California. A few seconds before an earthquake hits your area, you'll get an alert on your phone telling you the estimated magnitude, how far away the earthquake is, and instructions to drop, cover, and hold to protect yourself from falling objects.