Too bad Google gets the credit for the amazing https://www.shakealert.org system developed by the USGS and other public entities. Altering the user is the easy part, detecting the earthquake is the hard part.
Android also has a "detection" feature in non ShakeAlert locations. Android phones' accelerometer is used to detect earthquakes and warn other phones in the area: https://crisisresponse.google/android-alerts/
amf12|3 years ago
Android phones' accelerometer also detected the tremors: https://twitter.com/davey_burke/status/1585148438844694528
It's a pretty cool technical problem to solve while optimizing latency.
pythonaut_16|3 years ago
Detecting an earthquake early and alerting millions of people quickly are both hard problems, and both had to be solved for this to work.
Much of the hard work on Google's side just happens to overlap with other use cases that they've already scaled.
ilyt|3 years ago
"deliver same message to subset of subscribers" scales horizontally pretty easily.
canadaduane|3 years ago