Driver or passenger? Here's how Root makes the call.

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One of the most common questions we’re asked here at Root is: how do we know whether you’re the driver or passenger?

It’s a great question. Your Root car insurance rate is based primarily on how you drive, so it makes sense to wonder how we know you are behind the wheel.

The Root test drive starts with your smartphone.

We measure your driving behavior to give you the rate you deserve through the Root Insurance test drive. After you download the Root app and begin to drive, we collect high-frequency sensor data from instruments that already exist in your smartphone.

Here are some of those instruments in your phone that the Root app uses:


Global positioning system (GPS)

GPS is used anytime you open Google Maps or other navigation apps. In addition to latitude and longitude, your GPS collects data like speed, altitude, and the direction you're heading. (Whether you’re heading in the right direction is up to you.)



Your phone's accelerometer detects the acceleration of the phone, which plays a big role in determining whether you’re driving in a car. It shows if you’re accelerating too quickly or slamming the brakes abruptly—two of the main factors that determine your driver score.



Another sensor we use is the gyroscope. You'll find it in other technology, too, but the one in your phone helps to collect your rotation rates. Basically, it monitors and maintains your phone’s orientation during movement. The gyroscope can tell whether your phone is flat on a table or angled upward like you’re holding it. And it also helps us measure how smooth or sharp your turns are, which directly factors into your driver score.



Magne what? The magnetometer works with the accelerometer and gyroscope to detect your phone's orientation. It’s kind of like a compass because it measures your phone’s relation to the Earth's magnetic field.

All of the data collected through these instruments are put into an algorithm that accurately determines the motion of your phone. And the motion of your phone is different when you're the driver than when you're a passenger. During the course of your test drive, the motion from your phone develops patterns, and these patterns help us to make sense of the data. Once we’re confident with the measurements, your test drive ends.


Plane, train, or automobile? How we can tell the difference.

Different forms of transportation will transmit different data. So it’s easy to tell whether you’re driving, riding a bike, taking the bus or subway, or even flying.

For example, if you're riding a bike, the speed patterns will be much slower, as will the acceleration and deceleration rates.

Trains and buses also have distinct rates of curvature. And we can even merge the data we receive from your phone with a data set of train and bus routes. All of this data combined lets us know your mode of transportation.

Planes are a no-brainer. No one is driving that fast. (Especially in the air.)

The technology in our phones is finally smart enough to make car insurance fair. And that’s why Root exists. Now that you know how it works, see how much you could save with an auto insurance rate that’s based primarily on your good driving:

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