Phones and teen drivers can be risky together, but a phone app called EverDrive may save lives. So may technology that dealers can install on some cars, such as Teen Driver from Chevrolet. The digital devices track and score driver performance, letting new motorists – and parents – monitor speeds, fast starts, seatbelt use, entertainment system operation and texting.

Behind the development of those tools it is a stark fact: Vehicle crashes are the leading cause of death for U.S. teens. In 2015, 2,300 teen drivers died in 2015 accidents -- up 9 percent from the previous year. Drivers between 16 and 19 have a fatality rate three times higher than drivers over 20, says the Insurance Institute for Highway Safety.

Monitoring technology is a growing business, and not one aimed solely at teens. Companies keep an electronic eye on taxi drivers and truckers for safety, insurance and productivity reasons. SmartDrive Systems, a San Diego company, promotes its service for trucking fleets as a way to "eliminate the risky driving that leads to collisions . . . and reward safe driving." General Motors makes a digital Teen Driver system standard in most Buicks and available in nearly every other model. And GM's OnStar division has a million customers enrolled in its Smart Driver monitoring program.

Chevy’s Teen Driver lets parents set speed alerts and a radio volume limit, and has an in-vehicle "report card" that records distance driven, maximum speed, traction control, collision alerts and collision avoidance braking. The automaker’s website says: "Studies show that teenage drivers are more likely to make poor decisions like speeding or not fastening their safety belts than adults. . . About 93% of teen drivers play loud, distracting music behind the wheel."

Teen says: "Knowing that it's running in the background probably helps me drive a lot better. Because if I'm speeding, I'm like: 'Oh wait, my app is going to take off for that.'" – Sarah Gregory, 17, interviewed by CBS News

Insurance group says: "Immaturity leads to speeding and other risky habits, and inexperience means teen drivers often don't recognize or know how to respond to hazards." -- Insurance Intitute for Highway Safety

OnStar executive says: "If you’re feeling good about your ['smart driver' monitoring] score, you can opt-in to seek an opportunity to get an insurance discount. We're seeing that those customers are receiving up to a 30-percent discount." -- Christine Sitek