So the company notorious for killing projects is going to tackle infrastructure grade systems? I don't trust Google to tackle this problem.

Edit: Arstechina article seems to mention this: "only three were false positives. One of those was triggered by a different system sending an alert that vibrated a lot of phones"

- Feb 2016: third-party app starts doing it, so you had to go out of your way to install it but it may hit critical mass at some point. This is probably what I was thinking of --https://earthquakes.berkeley.edu/blog/2016/02/11/seismic-sen...

- Aug 2020: "Starting today", if the accelerometer shows a trace that "may be an earthquake, it sends a signal to our earthquake detection server, along with a coarse location". "we’ll use this technology to share a fast, accurate view of the impacted area on Google Search". Alerts were additionally issued in part of the USA based on government data --https://blog.google/products/android/earthquake-detection-an...

- Mar 2022: up to three USA states now with government data, rest of the world gets alerts based on crowdsourced data. Article mentions "2+billion Android phones in use around the world" (I take that to mean "2.1 billion Google Play Services devices"). If the quake is expected to be heavy, it "Will break through Do Not Disturb settings, turn on your screen and play a loud sound" --https://crisisresponse.google/android-alerts/

- Jul 2025 (this submission): nothing seems to have changed (still govt data for the same subset of the USA), but some stats on how it's going and that accuracy is improving. It notes that, to receive alerts, users must have "location settings enabled"¹ (and internet of course). About 1/3rd of the alerts are true positives that are also received before the shaking, but 85% of people found it 5/5 very helpful

¹ This confuses me. Surely Google doesn't get your location every ~10 seconds to know whether to send your device an alert; that's too battery-draining. Maybe it sends your location a few times per day~hour and they'll just use that? Because the alternative option, if the server sends "earthquake in {geojson polygon}" to all devices, the OS could just check your (last known) location without having to care about whether you want to provide location info to apps. I have the user-level location setting turned off whenever I'm not routing/mapping because why'd I want GNSS to be running... well, for this apparently, but it never told me this

https://arstechnica.com/science/2025/07/how-android-phones-b...

Do the range of detectable acoustic sources include military jets, drones, and bomb blasts (i.e., gauging effectiveness of targeting?) I don't know what I'm supposed to think of tech companies turning gadgets into remote-root physics sensors without user consent. Maybe I'm reflexively cynical; I can't trust a FAANG with yet another side-channel attack, *even if* the first (public) application is, on appearance, a life-saving unalloyed good.

Thats a decent amount of extra energy being used globally! And also everyone's batteries dying a little sooner.

I wonder what sample rate they have the accelerometer running at, and if it is just one axis to save power? Typically 8 bit single axis 1Hz sampling is ~10 microamps, but full 10 kHz 3 axis sampling could be 10 milliamps = 1000x more power use!