And still some stuff you can't customise on Android, or at least there are little niggles that can't be cured, any more than you can 'customise' an iPhone to use the FM radio functionality built into its Qualcomm modem.
When listening to Google Play or Spotify on Android, adjusting the volume from the handset results in some unpleasant 'plop' noises, even if playing through a Chromecast Audio device. Why would anyone want their music interrupted by this loud beeping? Strangely, this irritating behaviour doesn't occur in the BBC iPlayer Radio app. It just seems strange that Google have pushed Google Play music, developed and sold Chromecast hardware - yet haven't removed this rough edge, something that would be trivial for them to do yet impossible for a user to fix.