Android Auto
HearthShelf Mobile plays your audiobooks on your car's screen through Android Auto. It's a real native car player — you browse your library and control playback from the head unit, and audio keeps streaming from your own server.
How it works
The app ships a native Media3 MediaLibraryService — the playback engine Android Auto expects for audio apps. When you plug into (or wirelessly connect to) a car that supports Android Auto, the car sees HearthShelf as a media source, shows your library, and drives playback through that service. Your phone stays the brains; the car is the screen and the controls.
This is the audio-app model Google requires for car playback. HearthShelf implements it natively so playback, browsing, and lock-screen/car controls all come from one engine.
What you need
- The HearthShelf app installed and signed in on your phone — see Install (Android).
- A standalone build (the CI artifacts already are). A plain USB-tethered debug build stops when unplugged, so it can't run in the car.
- A car (or head unit) that supports Android Auto, or the Desktop Head Unit (DHU) for testing without a car.
Using it in the car
- Sign in on the phone first and confirm a book plays there.
- Connect the phone to your car (USB or wireless Android Auto).
- Open the media app list on the car screen and pick HearthShelf.
- Browse your library and start a book. Playback and progress stay in sync with your server.
Testing without a car
You don't need to sit in the driveway to test. Android's Desktop Head Unit renders the Android Auto interface on your computer against a connected phone or emulator:
- The DHU ships with the Android SDK (
extras/google/auto/desktop-head-unit). - The mobile repo includes an emulator AVD (
hs_auto) and deploy scripts set up for this loop.
See the repo's TESTING.md for the full DHU + emulator walkthrough.
Troubleshooting
HearthShelf doesn't appear in the car's app list. Make sure you're on a standalone build (not a USB-tethered dev build) and that you've signed in and connected a server on the phone at least once. The car only lists media apps that are installed and initialized.
It appears but the library is empty. The car browses the same library your phone does. Confirm the phone is signed in and can reach your server over HTTPS — the car has no separate connection of its own.
On iOS? iOS uses CarPlay for the same in-car experience — see CarPlay.