Some users on Reddit are reporting that Google has started rolling out the Android Auto update which overhauls the interface for the car and adds a dark theme that better fits with a car's interior. The update was announced back in May shortly before Google I/O kicked off, with the company announcing then it would arrive "in the summer". Two and a half weeks ago, Google announced that it would start rolling out "in a few weeks" and now it appears to be arriving to some users car screens.
As a reminder of what to expect, there are new colored accents throughout the new dark theme UI and fonts that are easier to read at a glance. There's a new navigation bar too, which makes it more convenient to access more functionality from the same screen. The area gives you access to your current navigation directions, music playback controls, and the new notification center and app launcher. The new app launcher makes it straightforward to find and access your available apps, while the notification center will house call and message notifications, giving you quick actions to interact with them.
There's also a new incoming call pop-up that lets users answer calls without taking them away from the rest of the UI. Finally, Google is also updating Android Auto to make better use of wider in-car screens. The additional space can show next-turn directions playback controls, and more.
Some Reddit users have said that they have been successful in forcing the update by going to Apps, force stopping the Android Auto app, then clearing data and cache which when launched offers a new "Try the new Android Auto" toggle, as seen in the above image. It must be noted that the UI for the phone app doesn't change, so you will have to confirm you got the update by connecting to your car's screen.