25/07/2026
Here's why some people got a phone alert about this morning's earthquake near Taumarunui - and others didn't.
Apparently Android phones (like mine) have a system of their own - which is triggered when it detects earthquake tremors. It doesn't supersede or replace the really loud official alert system we've become used to - it's just an added extra if you have an Android phone.
There was no official government Emergency Mobile Alert sent out in Auckland because, of course, there was no danger here.
Although this earthquake didn't affect us in Auckland, it's another reminder that we need to be ready for the unexpected - making sure we have emergency plans ready, and emergency supplies easily at hand.
๐ฑ Weโre getting a lot of questions about why some people got an alert on their cellphone before/during the Taumarunui earthquake and others didnโt.
๐ค Android cellphones have a function called the Android Earthquake Alerts System. Android phones have a built in accelerometer which picks up vibrations. If the phone senses movements which feel like an earthquake, it sends a signal to Googleโs servers which then do cross-checks from nearby phones. This helps to confirm if the vibrations from that phone and others nearby are actually caused by an earthquake, rather than just a few people dropping their phones at the same time.
๐ Youโll then get one of two warnings: โBe Awareโ for quakes below magnitude 4.5; or โTake Actionโ for magnitude 4.5 and above. The โBe Awareโ warnings do not override a phoneโs โDo Not Disturbโ system, while โTake Actionโ does.
๐ค While itโs a helpful system, it does have its flaws. It does not have the accuracy of the equipment GeoNet uses. This means it can get things wrong. This happened in Tรผrkiye in 2023, when Googleโs system significantly underestimated a 7.8 quake, which meant lots of people did not get the alert overriding their Do Not Disturb.
๐ฒ We do have the ability to send the Emergency Mobile Alert (EMA) to all cellphones - Apple, Android or anything else you may be using. However, we cannot do this before an earthquake. Earthquakes happen extremely quickly with little-to-no warning. By the time we would have logged into the system, written a message and decided where to send the alert, the quake would have been and gone.
๐
โโ๏ธWhile we can send an EMA after a quake, in this situation we did not. Thatโs because we are only supposed to send an EMA where there is significant threat to life, health and/or property. This threat should be actual, or very likely, for us to send an EMA. While there may be minor damage from the Taumarunui quake, it does not reach the threshold to send an EMA. The last thing we want to do is overuse the EMA system, as that could lead to people ignoring the alerts when they really need to pay attention to them.
๐ Weโll put some links in the comments to where you can learn more about the Android and EMA systems.
