Apple said at its annual Worldwide Developers Conference in San Francisco on Monday that outside developers would be able connect Siri to their apps, including car apps. That means that drivers would be able to, in theory, use Siri while on the road to send messages, make phone calls, and pay for gas through their car’s infotainment system.

Developer integration with Siri hinges on Apple’s in-car software platform, CarPlay, which integrates iPhones with car infotainment systems. The in-car software platform, which is available in a growing number of 2017 vehicle models and some 2016 models, brings the functionality and feel of a smartphone—and all those apps—to the vehicle’s central screen.

By giving developers access to Siri, the virtual voice assistant will now be able to control CarPlay apps, including ones from automakers that would let users set the climate controls and adjust the radio while they’re in their car.

Take a look at what Apple introduced at WWDC:

The Siri announcement was just a small part of Apple’s (AAPL) new mobile operating system, iOS 10, which will be available to developers as a free download to iPhone owners later this year. The operating system has an updated maps app that lets users see traffic and points of interest as well as improved photos that includes the ability to recognize faces.

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Earlier this month, Nissan announced that the 2017 Maxima would be equipped with CarPlay, the automaker’s first vehicle to have the software platform. Most major automakers—with the notable exception of Toyota—are adding CarPlay and Google rival Android Auto to new models. Automakers Audi, Cadillac, Chevrolet, Ford, GMC, Honda, Hyundai, Kia, Mercedes-Benz, Volkswagen, and Volvo are just a handful of companies to offer CarPlay now.