Android Auto is still somewhat of a niche product. There's really only two ways of having Android Auto right now. One is to buy a new car from a manufacturer that has already gotten Android Auto into their models. The other is to buy a third-party head unit from Pioneer or JVC Kenwood. Which can cost you near $1,000 to have installed when everything is all said and done. But Google is steadily improving the product, and have just released version 1.5 of the Android Auto companion app. And in looking through the code in the new version of the app, we can see that there are a few new features coming to Android Auto in the future.
One of those features is a Parking Assistant. This is something we all need. How many times have you driven somewhere and come out of the store or restaurant and wondered where you parked? Now Google has had a parking card in Google Now for quite some time now (although it's not 100% accurate, at the airport it says I parked on the runway). But with it working with Android Auto, it should be able to tell where your phone disconnected with the car's Bluetooth, and that is the place you parked. You will also be able to find on Google Maps where exactly your car is. Making things much easier.
Something else found in version 1.5 of the Android Auto companion app is the handwriting keyboard. Now Google has tried to make typing on Android Auto as unnecessary as possible. By doing everything with voice commands, because we should be keeping our eyes on the road. However that's not perfect. With setups in some cars, it would be easier to handwrite letters and words then to type them in. The Audi Q7 is a good example. As Audi has opted for using a rotary knob to scroll through things, and a touch pad in the center console. Handwriting the letters on the touchpad would be much easier then scrolling through the entire alphabet in the Audi Q7.
The companion app was updated on December 9th, so everyone should have the most up to date version already. These features aren't yet available in the update, but are coming soon.