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Recently they had a significant country wide false alarm in Israel at 3AM... There was a emergency alert cell broadcast (similar to amber alert), which caused everyone to move their phone at the same time, which was falsely detected as an earthquake, which caused an Android earthquake alert to be sent to all phones in Israel 30 seconds later. I guess they didn't plan for this scenario
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"
I heard it was the cell broadcast which caused the phones to vibrate at the same time, not people picking them up.
Note that those are three completely false events. The survey results Google published show 15% of people not feeling any shaking (neither strong nor light). That's still a good figure, but reading there were only 3 false positives gave me the impression that you're basically always in for a ride when you get the alert and it's not that miraculously accurate either
Surprised they don't do some signal processing on all the IMU signals to see if they correlate (to within a rotation matrix), and if the timing of shaking at different locations is consistent with the distance to some (solvable) epicenter.
The whole country moving phones in random directions at exactly the same time isn't what an earthquake signature should look like.
I don't get it. I thought earthquake alerts were meant to trigger _before_ the earthquake arrives. If it happens 30 secondes after detecting vibrations, not considering the false positive, it can only mean "hey, you just felt, or are feeling an earthquake, hope you're sheltered".
Somewhat relatedly, I support a service with global scale traffic. Whenever there's an earthquake in APAC, we get a traffic spike, like 100x normal for that time of night. I'm pretty sure it's incoming alerts waking people up / checking where the epicenter is and if they need to run from any tsunami or flooding, but it's still really hard to scale that kind of thing up for regional demand when it spikes that hard!
I was thinking the same thing. A taylor swift concert where she tells everyone to sway their phones in unison might trigger this
Kind of ironic that the alert caused the earthquake warning
Maybe it was due to the blasts from their own ordenances
This is really cool, and it smells like old-school Google, in a good way, like "let's do this because we can". It feels like it's been a while since something coming out of Google Engineering is meaningful and not designed to unlock new existential creeps, so, well done I guess.
No ads, no creepy monetization angle (at least not yet), just a genuinely useful system that leverages something only Google could realistically pull off. Feels rare these days, but really nice to see.
I no longer live near any epicenter but this was the biggest feature I admire as a non-Android user.
A few years back I was woken by a shake in HongKong. To confirm was a quake I found my Android phone and sure enough Google had registered a quake. It was one far inland and <5 IIRC. Creepiness or not as someone who helped after Sichuan 2008 quake these kind of systems can save lives.
> "Of those roughly 1,300 events that triggered alerts, only three were false positives. One of those was triggered by a different system sending an alert that vibrated a lot of phones, something that should be relatively easy to compensate for in software. The other two were both due to thunderstorms, where heavy thunder caused widespread vibrations centered on a specific location. This led the team to better model acoustic events, which should prevent something similar from happening in the future."
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.
I have received a few earthquake alerts (Greece). one was for a significant 5.2 earthquake about a month ago, and the notification arrived about one minute earlier or so. It woke me up , and i was able to experience the entire duration of the earthquake. Pretty cool if they were using the new system and i was impressed at the time.
Curious if the alert mentioned how strong the shaking would be, or was it more of a general "earthquake incoming" type message?
Last time we had a reasonably powerful one in Portugal, I grabbed my phone the house was still shaking and it already had the Android warning!
I was surprised as I didn't even know it was a thing.
I was also a bit spooked as it was in the ocean, near the coast, and when I turned on my FM radio as we were always taught in school, all I heard were pre-recorded music programs.
Turns out it didn't meet the threshold for a warning so the authorities didn't issue any message about tsunami danger. I think they should've anyway, as I wasn't the only one that had that thought.
yeah I've ran into bunch of people who were scared for real and drove up to higher elevation in the middle of the night.
If you'd search online you could have known quickly there was a negative Tsunami notice, but I get that this is just not feasible for everyone (or everytime).
Feel like the severe weather SMS etc are working quite decent, I wish they'd expand that for those sort of things as well (like there was an earthquake, this is what you should do next).
The Android notification was a bit odd, because it's not trivial to get back to that notification if you've just skipped/acknowledged it.
Few months back we experienced an earthquake. I got an alert on my Android, which at first I was confused about but took me a second to process that there is a possible earthquake and then we ran out and it was a 5.2 magnitude earthquake. So it is much improvement over the last time I experienced an earthquake and only knowing later that it was one about 3.5 or so.
Even a few seconds of warning can make a big impact, especially if you're indoors
Pretty impressive use of existing infrastructure for public safety. Turning billions of smartphones into a global seismometer network is one of those "why didn't we do this sooner?" ideas. Sure, it's not a replacement for dedicated seismic systems, but when most of the world doesn’t have access to those anyway, this feels like a huge leap forward
As someone who lives in an earthquake prone area it's hard to explain the spooky feeling of receiving a message about an impending earthquake 2-3 seconds before it hits. To be honest it doesn't feel helpful. There's never enough time to react properly.
I've only ever experienced a big earthquake once, which was in Bangkok a couple of months ago. And if I had known it was an earthquake, I probably would've reacted differently. Not knowing what was happening, and genuinely thinking my building was about to collapse on top of me was one of the scariest feelings in my life.
So the use cases like "get down from a ladder" aren't really likely to be achieved in real life? When I'm working on a ladder, I'm not going to be checking phone notifications anyway.
I thought this was ancient but apparently not. Searched back a bit:
- 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
There is also the Earthquake Network (EQN) app that works on very similar principals to Google’s system - phones monitor their MEMs accelerometers, when they are left charging with their screen off, and when enough neighbouring phones detect vibrations simultaneously an earthquake is detected and apps nearby are alerted. It’s been running since 2012.
I wouldn't be surprised if coarse location on Android doesn't even bother turning on the GPS. You can do a lot with cell towers and wifi ssids
> 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?
Why not?
You can use router IP address for location and WiFi to send. Minimal power consumption.
This relies on the accelerometer being always turned on - which it typically isn't when the phone screen is off.
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!
All your questions/assumptions are answered in the linked paper supplementary material: 50hz, 3 axis, only when charging. Accompanied with actual sample plots for various distances from epicenter, showing p waves and s waves.
Did people opt into having their data analyzed by Google? They seemed to have skipped over that is super important part about consent.
As always.
Last time I received it I was on a 14th floor and I was terrified. Longest seconds of my life while I waited the P wave to arrive.
Had a fun experience of receiving "EARTHQUAKE ALERT. THERE WILL BE SHAKING. IT WILL BE STRONG" jolting me out of a deep slumber in Japan at 3am on a recent vacation. My wife asks the question on both of our minds: "here? back home? is there anything heavy over the bed?"
I think we both would have assumed it was for back home in California if not for the fact that we were in a country that ALSO has earthquake and tsunami history.
By the time she asked I just said "well, either way, if we don't feel anything in the next few seconds, we're fine." and then went back to sleep.
In retrospect, I didn't think to wonder where the alert came from. I suppose it must have been from the MyShake app on our iPhones which are connected to the ShakeAlert system. But maybe it was the Wireless Emergency Alert system? I'm not sure how that works overseas.
Is there a way to get alerts or contribute data with IOS?
I'm still hoping someone makes an earthquake detection system where the data is just derived from people posting "Earthquake?" on Twitter/Threads/Facebook/Etc. Plot the geotagged tweets and it seems easy to get both the location and magnitude.
Call me a hater but I think Google has too much might already. Give em more leads to... you know the story.
I was about to install the app to help... but I guess this is part of the general dragnet so no need?
> To receive alerts, users must have Wi-Fi and/or cellular data connectivity, and both Android Earthquake Alerts and location settings enabled.
Enabling location settings is a global configuration. Can’t this be configured just for this purpose?
From the coverage area map, it seems japan and indonesia (two countries with lots of earthquakes) aren't covered by this service. I wonder why.
Is this app native to Android OS xx ??
Is it by default on ? How can i check if its actually working ?
So many questions! None detailed in the article...
You could probably also use this system for seismic imaging too.
What exactly is their prediction model?
Really curious to know.
Is there an iOS app for it?
Obligatory XKCD: https://xkcd.com/723/
Company that tracks people to send them ads wants you to sign up for some 10 year old technology for .. saving lives!
> Android Earthquake Alerts: A global system for early warning
Fixing bugs in Google products is no fun. Better make something else what nobody needs.
>"[...] and builds user trust with each successful alert"
So the company notorious for killing projects is going to tackle infrastructure grade systems? I don't trust Google to tackle this problem.