Three students meet up at USC and bond over a passion for technology, spending their nights and weekends hacking and eating takeout. Fast forward several years, and now they’re market leaders, signing up users for their mobile app almost as fast as they can build the software. Sound familiar?

Probably. But most startup founders haven't trolled the Academy Awards, scanning celebrities' cell phones to see which ones have security flaws. That's how Lookout Mobile Security got a profile in the New York Times, positioning the founders as experts on mobile security.

In 2004, prior to founding Lookout, John Hering, James Burgess, and Kevin Mahaffey discovered a security flaw in Bluetooth technology that allowed them to remotely control phones.  Attempts to alert phone manufacturers to the issue fell on deaf ears.

So, to get their attention, the crew built custom software and hardware that allowed them to extend the range of Bluetooth from 100 meters to 1.2 miles. They put the gear in a backpack, walked the red carpet at the Academy Awards,  scanned all of the devices in range, and highlighted all of the devices that could be hacked. The stunt got the budding entrepreneurs considerable publicity. It gave us a platform to have a conversation with all the major OEMs and operators,” says Hering, the company’s CEO. “That led to the founding of the company.”

Today, the Lookout Mobile Security app protects the smartphones of some 20 million users from malware, spyware, and privacy breaches. If a phone is stolen, the app, which is available for both iPhones and Android devices, enables users to locate their phones, lock them, and even sound an alarm. The limited version is free; the pro version is $2.99 per month or $29.99 per year.

Mahaffey, the company’s chief information officer, says the app’s secret sauce lies in its cloud infrastructure. While most antivirus software can be an energy suck and slow down the device it's meant to protect, Lookout offloads most of the processing to the cloud. If we’re doing our job right, users don’t even notice it,” Mahaffey says.

Since its founding, the company has raised more than $75 million from Khosla Ventures and Andreessen Horowitz. Lookout has also struck partnerships with Sprint and T-Mobile, as well as T-Mobile’s European sister company, Deutsche Telecom. Hering says his own personal watershed moment occurred a couple of years ago, when Verizon ran a commercial during the World Series featuring the Lookout app.

“That was when my family actually understood what I did for a living,” he laughs. “So it’s not just this technical jargon, but something that impacts everyone.”