Can the Android app also connect to my self-hosted subsonic server? Or only to Astiga accounts?
Only to Astiga. The app also implements functionality that does not exist in Subsonic or other implementations, such as artist lists, which makes it incompatible with other servers.
Thanks, that makes sense. As the Astiga app is the only Android Auto compatible subsonic app I've found I was hoping to be able to connect with my server as another option...
The Google Play store version of DSub supports Android Auto too as far as I'm aware.