Why Spotify does not just show HomePod
HomePod is primarily an AirPlay speaker. Spotify on Android does not turn the phone into an AirPlay sender, and HomePod is not a normal Bluetooth speaker you can select from Android settings.
That leaves one practical path: capture the playback audio on Android and stream it over the local network to the speaker.
How to use Bridge Audio with Spotify
Start Spotify on Android, open Bridge Audio, select the HomePod or the room target, and grant the capture permission when Android asks. Once the stream starts, Spotify stays the player and Bridge Audio handles the route to the speaker.
Use the app's free test first. If the room plays correctly and volume behaves as expected, unlock unlimited playback with the in-app purchase.
What metadata and controls can do
Bridge Audio can show richer now-playing context when Android exposes notification metadata and the user grants the related permission. Without that permission, the stream can still work, but the app may show less track information.
Volume and playback controls depend on the receiver, Android media session behavior and the current app. The core job is routing sound to the HomePod; richer controls are handled when the platform exposes them cleanly.
Good first test tracks
Start with a regular downloaded or streamed music track, not a video with protected playback. Keep the phone unlocked for the first test, confirm the speaker target, then lock the phone and verify the foreground notification keeps the capture alive.
If the phone speaker also plays, lower or mute local media volume after connecting. Android capture and local playback are separate device behaviors, and some phones handle this differently.