Spotify is generally what people open first when they listen to music. There should be a feature that when you open Pacemaker it syncs with the song that was previously playing on Spotify and continues to play without interrupting the song (with some latency, I assume). The reason that keeps stopping me from using this app is that I’m already listening to a song I like on Spotify and have to either look for another song or go find the song I was already listening to when I open Pacemaker.
Overall, I think Pacemaker is a great app with lots of potential!
Thanks for the suggestion. Today we're using some legacy technology to access Spotify songs which means knowing what you're listening to elsewhere isn't possible. The good news is that we hope to soon move to a newer technology meaning things like this might be possible. Can't promise that we'll ever add such a feature but we'll certainly consider it.