According to people familiar with the plans, Apple is working with car makers on updated versions of car center consoles that could attach to iOS devices like the iPhone. Specifically, an iPhone could be plugged into a car and an optimized, redesigned version of Apple Maps will appear on the car’s built-in display instead of a proprietary GPS system found in many cars.
Drivers would likely be able to control Maps with Siri 'Eyes Free' which is already being integrated into several vehicles.
The new feature is reportedly 'based on technologies in iOS 7'; however, Apple could face numerous roadblocks to release including: car-based testing, required improvements to Apple Maps and Siri infrastructure, and negotiations with car manufacturers.
It's still unclear if Apple will debut the new functionality at WWDC or at an event later in the year. Apple is expected to unveil iOS 7 at WWDC which is said to feature a 'very, very flat' user interface.