PayPal has taken another step toward the mobile world with its integration into the mobile-booking application of car-service company Uber Technologies, according to Bloomberg News. Starting today, Uber users in the U.S., France, Germany, Italy and the Netherlands can now pay with PayPal. Riders who do so before Nov. 28 will get $15 or 15 euros toward their next trip.

PayPal President David Marcus, posing as an Uber driver and chauffeuring reporters around San Francisco, acknowledged that PayPal, which was acquired by EBay in 2002, has been slow to enter marketplaces that cater to mobile-savvy users and developers.

"Our experiences inside mobile apps were not meeting the bar a year ago," he told Bloomberg. "It's important to be where disruption occurs. You want to partner with the companies creating an amazing consumer experience."

PayPal's software has been criticized for being hard for merchants and developers to use. For the Uber deal, PayPal has developed a new mobile SDK for Android and iOS that it will release early next year, according to TechCrunch. With the SDK, the Uber app won't redirect to PayPal and won't require a login to use PayPal.

Learn more about in-app payments.