It was the first (only?) app where I was baffled at the features compared to the price. It's a joy to use. If you self-host music, it beats the competition by miles
I wish sonos had better interoperability, but I did discover if you make a group of speakers and then cast to the "primary" speaker with symfonium, it broadcasts to the whole group.
Was my only issue with it, but that's 100% a "sonos is shit" problem, not the app.