Since I would be using a phone app to tell the streamer what to play, why would the sound quality improve?
This is the same as using your TV remote to change channels or adjust the volume. The actual picture and sound quality is handled by the TV, the remote has no bearing on it.
Get a Bluesound Node 2i, but make sure you DO NOT play via the bluetooth interface, or even Apple Airplay. Using direct ethernet or wifi with the Bluesound remote app will give you the sound quality that will be substantially better than the other two options.