Android Auto is pretty cool, but the requirement of an expensive headunit for your car (or a new car that shipped with Android Auto support) set the barrier of entry pretty high. Thankfully, Google added the ability to use the Android Auto interface on your phone last year. Still, if you want the full Android Auto experience, a compatible Sony head unit is currently $398 ($100 off) from select sites.
The Sony XAV-AX100 has a 6.4" LCD display, Bluetooth compatibility, and an AM/FM tuner. It also fully works with both Android Auto and Apple CarPlay, so if you switch away from Android devices at some point (or you're already rocking an iPhone), it won't become useless.
The sale appears to be live on several sites, including Amazon, Best Buy, Walmart, and Newegg. Let us know in the comments if you see it anywhere else.