California Warned 2.2 Million People Via Phone Alerts Before Earthquake Hit

The first demonstration of a straight-to-phones earthquake warning system reached mostly Android users.

David Lumb Mobile Reporter
David Lumb is a mobile reporter covering how on-the-go gadgets like phones, tablets and smartwatches change our lives. Over the last decade, he's reviewed phones for TechRadar as well as covered tech, gaming, and culture for Engadget, Popular Mechanics, NBC Asian America, Increment, Fast Company and others. As a true Californian, he lives for coffee, beaches and burritos.
Expertise Smartphones | Smartwatches | Tablets | Telecom industry | Mobile semiconductors | Mobile gaming
David Lumb
2 min read
California Governor Gavin Newsom gettyimages-1421661720
Jerod Harris/Getty Images for Vox Media

On Tuesday, 2.2 million Californians in the San Francisco Bay Area got phone alerts warning that an earthquake was coming before it hit, the first use of a new statewide warning system that goes straight to people's smartphones.

There were no reports of damage or injuries from the 5.1 magnitude earthquake, which hit a suburb of San Jose, California, but the system still alerted residents up to 19 seconds before they felt tremors, according to a press release. The vast majority of alerts -- 2.1 million -- went directly to Android phones, as the state government had negotiated directly with Google to integrate the alert tech into the operating system.

About 95,000 other users, including iPhone users running iOS, received the alert through California's official earthquake warning app, called MyShake, which receives alerts from California's Office of Emergency Services. The state has been in talks with Apple, but neither side has announced when or if this functionality will be included in its phone OS.

"The state and federal govt continue to work closely with technology partners and we remain hopeful of the technology being included across all operating systems in the near future, including iOS," OES spokesperson Brian Ferguson told CNET.

The alerts are based on readings from ShakeAlert, which is operated by the US Geological Survey and OES to analyze seismic activity and predict which areas could be affected. If the system's algorithm predicts an earthquake of 4.5 magnitude or greater, which is when earthquakes start to become dangerous, according to Ferguson, then OES sends the alerts out -- ideally with enough time for people to prepare. 

"When it comes to earthquakes, seconds can save lives," Gov. Gavin Newsom said in a press release. Newsom announced the creation of the earthquake early warning system in 2019, and the following year, he unveiled the state's partnership with Google to send its alerts directly to Android phones. Alerts are available on Android 5 and above, though users will need to have location switched on, Earthquake Alerts enabled, be receiving data (either over a cellular connection or Wi-Fi) and be located in a supported region.

The state's MyShake app has been downloaded by about 2.1 million users, and OES' system only alerts users who are in areas that would be affected by the current earthquake -- in Tuesday's case, that's 95,000, or just under 5% of the user base. The app also feeds back into the statewide monitoring system by notifying when a phone feels the earthquake hit, adding more data that can further refine its predictive algorithms and, in turn, the capability to notify Californians of an incoming temblor.