The magnitude 5.3 earthquake which hit the lower North Island and upper South Island on Tuesday gave some a bit of a shock - but not for the reason you might think.
More than 17,000 people reported to GeoNet they felt the earthquake with the majority saying it was 'weak' or 'light'.
But an unspecified number got a pre-warning that their world was about to be shaken thanks to an early warning system on their Android phones.
"How cool is it that my Android phone alerted me of an incoming earthquake a few seconds before it happened?" one user wrote on Twitter.
"That's a great way to use technology, Google!"
Another wrote they got the notification on their phone 30 seconds before they felt the earthquake.
The early warning system was introduced to New Zealand in April, with the country being among the first in the world to get access to the technology.
It works because phones can detect the seismic waves indicating an earthquake may be happening using their built-in accelerometers.
A signal, including a rough location, is then sent to a central server, which then uses other phones to figure out if an earthquake is actually happening, where it is and its magnitude.
At the time, Android product manager Boone Spooner said the company "hope to provide people with the advance notice they need to stay safe".
Today's feedback on social media suggests that's true for at least some Kiwis using Android phones.
There is currently no comparable system for Apple iPhone users.
The system is separate from the National Emergency Management Agency system, which has alerted New Zealanders to COVID-19 lockdowns as well as tsunamis and earthquakes through their mobile phones.
The Android Earthquake Alerts System was first triggered in Aotearoa in May after a magnitude 3.4 quake in Christchurch.
