Los Angeles just released an app that can predict earthquakes up to 90 seconds in advance, and it could one day save countless lives

• Los Angeles is the first US city to publicly release an early earthquake warning app.
• Known as ShakeAlertLA, the app is available for download now. It aims to alert residents in the event of a magnitude 5.0 earthquake or greater.
• Though earthquake warning apps have found some success in Mexico and Japan, researchers aren't sure how effective ShakeAlertLA will be at alerting a large number of residents.

At any moment, a magnitude 8.0 earthquake could ripple through California, toppling its infrastructure, cutting off power, collapsing buildings, and taking lives. Scientists refer to the quake as "The Big One," and they say it's inevitable, though no one is quite sure when or where it will happen.

The quake could come from the San Andreas Fault, which stretches almost the full length of California. It's possible that the Big One could occur near San Francisco, though scientists have said the fault near Los Angeles is "riper, more ready to go."

Read more: Earthquake maps reveal never-before-seen detail about threats to buildings and people - here's who's most at risk around the world

A few seconds of advanced notice would give citizens enough time to duck and cover, and reduce the likelihood of injury. Tens of seconds could allow time for life-saving measures, like a surgeon finishing an operation or an industrial worker shutting off a gas pipeline.

Earlier this week, Los Angeles became the first US city to release an early earthquake warning app to the public. The app, known as ShakeAlertLA, relies on a system developed by the United States Geological Survey (USGS), which has been refining the technology for years. LA residents are able to receive earthquake alerts on their Android and Apple smartphones - a rollout made possible by a contract with AT&T.

For many years, researchers have been brainstorming a way to alert residents in the event of the Big One, or even a smaller earthquake that could potentially cause damage.

Though other US cities have yet to reveal the same technology to citizens, early warning apps have already found some success in nations like Mexico and Japan.

The timing of an alert depends on both a quake's magnitude and a person's location. Warnings could range from two seconds to 90 seconds of advanced notice, said Kate Hutton, a coordinator at LA's Emergency Management Department.

But according to Richard Allen, the director of the Berkeley Seismological Laboratory, which developed a key algorithm for the ShakeAlert system, earthquake researchers aren't entirely ensure whether the warning will work as planned.

"We don't know how quickly and effectively apps like ShakeAlertLA, or any app for that matter, could deliver the alert to a very large number of people," he told Business Insider. "What the city [of LA] is doing is trying to push the envelope by putting the app out there, and we'll see how it performs."

LA Mayor Eric Garcetti admitted as much to reporters in October.

The ability to save lives by delivering a few seconds of advanced notice "will not happen the first day we launch," he said.

Hutton agreed that the technology will have to be refined with time, but said that the USGS made sure the app was working well before unveiling it to the public.

"This is relatively new system for us," she said. "What you don't want to have happen are false alerts that … people don't trust anymore or a situation where it doesn't alert when a major earthquake is happening."

To account for this, the app only issues an alert when an earthquake's magnitude is at or above 5.0 - the point at which minor damage is possible.

Allen estimated that there are 100 times as many 5.0 earthquakes as there are 7.0 earthquakes.

With time, he said, residents could get used to the idea of an early warning system, and learn how to protect themselves in the event of the Big One.

"Hopefully, when we do have a big earthquake, the system will be working very smoothly," he said.

As a Bay Area resident, Allen said he "fully expects" there to be major earthquake in his lifetime, though he doesn't believe in inciting chaos.

"It's not about panicking," he said. "It's about being cautious."

Hutton shares this view.

"One day, possibly very soon, we will have a major, major earthquake in Southern California," she told Business Insider. "We hope people use this app as a chance to think about not just what they would do in the 30 seconds before a quake, but what they can do now to prepare."