You can now play any Pandora station you want from your Uber driver's sound system

Uber riders can now play Pandora radio stations through Uber's iPhone app, the companies announced Thursday, in a deepening of their partnership.

In June, Uber rolled out the ability for its drivers to add Pandora to their app, along with a 6-month ad-free trial. Pandora's Nick Marcantonio told Business Insider that "hundreds of thousands" of drivers have enabled the feature so far, and they have played over 4 million hours of Pandora music.

"The adoption has been really strong [on the driver side]," Uber's Holly Ormseth said, echoing the sentiment.

Now riders will be able to tap into the sound system of any driver that has his or her music system connected to the Uber app. This feature will sit beside Uber's ability to let riders who have Spotify Premium play music in a similar way, though it will extend to both free and paying Pandora customers.

Here's how it will work. If you request a ride from a driver that has music turned on, a little window will pop up and show you what music is playing currently. You can then select whatever Pandora station you want, and it will start playing as soon as you step into the car.

This seems like a potential recipe for social disaster. Maybe you and your driver don't share the same taste in bad pop music. But Ormseth says that, in the time Pandora has been available for drivers, they have consistently asked to let riders have control of the music. She does admit they were a bit worried about it at first, however.

But at the end of the day, it's a customer service business, and that won out in feedback, she said.

As a rider, to work the feature, you must have a Pandora account, either free or paid. You can't simply control the driver's Pandora account, since Pandora didn't want you messing with your driver's personalization, Marcantonio explains. The best case scenario for Pandora is likely to get the service back on the radar of users who are pretty inactive.

For Uber, the move isn't about favoring Pandora, but rather about integrating more and more services into its platform. Ormseth says that Uber wants to provide as many entertainment options as possible for riders. Right now that means Spotify Premium and Pandora, but in the future one could imagine Netflix on a TV in the back of your self-driving Uber.