Google has turned more than two billion Android smartphones into a crowd-sourced global earthquake detection system — a bold initiative that is already alerting millions of people across 98 countries, according to a new report published in Science and highlighted by Nature.
Between 2021 and 2024, Google’s Android Earthquake Alerts System detected over 11,000 earthquakes using motion sensors embedded in mobile phones — a feat traditionally left to highly sensitive and expensive seismometers. The analysis, published this week, shows the system performed on par with conventional seismometers, according to Google’s research team.
The findings mark a major milestone for the system first announced in 2020. By analyzing subtle accelerations in Android phones — which are equipped with accelerometers by default — Google developed algorithms capable of identifying seismic activity, estimating magnitude, and issuing timely alerts. These alerts, including urgent “TakeAction” messages, are sent directly to users near the quake’s epicenter.
“It’s very impressive,” said Allen Husker, a seismologist at the California Institute of Technology, in a statement to Nature. “Most countries don’t have an earthquake early-warning system, and this can help provide that service.” Still, Husker and other researchers caution that greater transparency is needed. They urge Google to provide independent scientists and public safety agencies with more access to the system’s algorithms and data — most of which remain proprietary.
According to the report in Nature, Google acknowledges these concerns. While citing privacy issues as a barrier to sharing raw motion data from users’ phones, the company says it is committed to being as transparent as possible. “That really is the origin of this paper,” said Richard Allen, a seismologist at the University of California, Berkeley, and visiting faculty member at Google. “I hope the community will recognize that and appreciate that.”
The power of Google’s system lies in scale over precision. While traditional seismometers provide high-fidelity data, Android phones — numbering in the billions — collectively offer unmatched coverage, especially in regions with no formal seismic infrastructure. Each phone contributes motion data that, when combined with inputs from others nearby, helps pinpoint an earthquake’s origin and severity. Algorithms account for geographic variations, building construction, and differences across phone models.
However, challenges remain. The system initially underestimated two massive earthquakes in Turkey in February 2023, triggering 4.5 million alerts. After revising their models and upgrading algorithms, Google said the system would now have sent more accurate and urgent warnings to nearly 10 million users.
“This shows they have been working to improve the system since 2023, with tangible positive results,” said Harold Tobin, a seismologist at the University of Washington. But Tobin echoed calls for more openness, especially since the system touches on public safety. “For a public-safety system like this one, the Android team has a responsibility to be very transparent about how it works,” he told Nature.
Google, for its part, emphasized that the mobile alert network is meant to supplement official earthquake warning systems, not replace them. In a statement to Nature, the company called the alerts “a supplemental service” that helps extend coverage to underserved regions — many of which previously had no early-warning systems at all.
With the number of people receiving real-time earthquake alerts having increased tenfold since 2019, Google’s initiative demonstrates the immense potential of everyday technology in crisis detection — and highlights the evolving role of tech giants in global public safety.
