In its current state, Spotify on Gear S3 after the Tizen 3.0 update is unusable: You can listen to and play music but when you close the app (using the "recent apps" button to close the application). If you are done listening to music, and decide to make a phone call, use S. Voice or anything that requires the speaker, spotify will start to autoplay after the call is over. This can literally be 6 hours after you have closed spotify.
Example scenario: I went for a run yesterday morning. Around 4 hours later I made a phone call using my watch. After the call hung up, spotify started blaring the song out of my watch speaker while at work. The *only* way to stop the playback is to uninstall the app. There needs to be a way of stopping (not just pausing) music so it does not autoplay *every* time you use the watch speaker for anything.
We just wanted to let you know that the right folks are aware of this, and taking a look.
Right now, we're not able to provide an exact timeline for a fix, but we'd recommend always keeping your Spotify app up-to-date to ensure you're on the latest and best version.
We'll continue to keep you posted here with any updates.
Many thanks for your patience, and understanding. /M