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Bad Drivers Are About to Be Outed by a Dashcam App

Startup Nexar aims to profile bad drivers and warn you about them before you encounter them on the road.
June 23, 2016

I’d rather be sitting in the car with Eran Shir than driving the car in front of him, especially if I’m doing something I shouldn’t be while behind the wheel.

Shir is the cofounder and CEO of a startup called Nexar that’s making a smart dashcam app. It records your trips and uses phone-based machine learning and the sensors on your smartphone to do things like figure out when you’re in an accident and automatically upload a video of it to the Web.

In the coming months, Shir says, the company—which just raised $10.5 million in venture funding (it’s raised a total of $14.5 million thus far)—plans to start using this kind of information to warn other users when, say, a car up ahead suddenly slams on its brakes or a dangerous intersection is coming up. Its app is free and currently available only for the iPhone.

Nexar’s iPhone app records your drives and can detect incidents like sudden hard braking.

But the startup is also intent on using its technology to profile drivers in hopes of making roads safer. The app gathers the license plate numbers of cars you pass on the road and captures incidents such as people cutting you off in traffic, Shir says. Nexar is using this information to build a driving score for each vehicle.

That way, late this year or early next the app can start alerting you when you’re close to someone it considers a bad driver. The company acknowledges that this may make some people uneasy about privacy protection, but it says it’s legal in the U.S. because the license plates are being photographed on public roads and because both software and people will analyze uploaded events and weed out the junk.

“When we are telling you ‘We think this car is dangerous,’ we think that strikes the right balance between public good and privacy,” Shir says. “We are definitely not interested in knowing where you’re coming from and where you’re going.”

Driving me around in his rental car in San Francisco, Shir demonstrated how Nexar can use the accelerometer, gyroscope, and other sensors in the phone to determine if you brake hard or get in a crash. Video of that moment is swiftly sent to Nexar’s servers (that way it’s preserved in case something happens to your phone soon afterwards). You can also tap the phone’s screen or utter a voice command to tell it to mark an incident at a specific moment.

The dangerous-driver feature takes the “How’s My Driving?” bumper sticker to a whole new level. Using a feature Nexar is slowly rolling out, the app displayed the license plate numbers of the cars around us along the top of the phone’s screen; you tap on the screen or speak to report any dangerous moves those cars’ drivers made, like running a red light.

Shir and cofounder Bruno Fernandez-Ruiz believe Nexar’s services can help reduce traffic accidents, which totaled about six million in the U.S. alone in 2014 (resulting in nearly 30,000 deaths), according to the most recently reported data from the National Highway Traffic Safety Administration. And they could help improve autonomous-vehicle technology, too, by giving self-driving cars a better sense of how people actually drive. 

Shir says that since the app was publicly released in the spring, it has gained “tens of thousands” of users. Over time, Nexar users have logged five million miles on the road and reported 300,000 incidents in cities including San Francisco, Tel Aviv, and New York.

Dan Work, an assistant professor at the University of Illinois at Urbana-Champaign who researches data analytics for urban transportation systems, says that this kind of data is “stuff you would die to have” for transportation engineering. Typically, data on car accidents consists of police reports, but that doesn’t include the near misses that Nexar could capture, he says, and seeing these things could help cities make intersections safer and help keep drivers better informed.

For now, though, he’s not so sure that it would be useful to know about bad drivers nearby.

“That needs some larger user base to scale to actually give me those warnings in a way I think would be relevant,” he says. “But I don’t think that’s impossible.”

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