Browse and search
Artists, albums, playlists, genres, favorites, and whatever else the server exposes.
OpenSubsonic compatibility
For Navidrome and the rest of the Subsonic family.
Headroom uses the OpenSubsonic API, the same one Navidrome, Gonic, Airsonic, Funkwhale, and Nextcloud Music expose. Navidrome is well tested. The rest should work, and I want to hear about it when they don't.
Compatibility
Same API, different servers.
Navidrome is where most of my testing happens. Airsonic forks, Gonic, Funkwhale, and Nextcloud Music each implement the API a little differently, and I haven't tested them nearly as much.
Sound
Gapless, crossfade, ReplayGain, parametric EQ, and AutoEQ, processed on the phone.
Downloads
Take albums offline. Downloads pick up where they left off after a dropout or a relaunch.
Reports
When a server does something unexpected, the in-app report includes what it sent back, minus your credentials.
One caveat
Compatible isn't the same as tested.
Versions and optional extensions vary a lot between servers. I'll list a server as supported once a real install passes the core flow on both iOS and Android, and not before.