Loving PlexAmp for iOS

Sorry if this has been addressed before but is there a way to use plexamp as a controller of other plex apps? I would really like to be able to use plexamp as a remote and have it use another plex app (plex, plexamp, etc) as the player. I believe this used to work in the old plexamp as shown here:

Additionally I see that controller functions were mentioned in the medium article announcing plexamp 3.0 but I don’t see anywhere in the UI to choose the player output device to ‘cast’ to.

If I use the regular plex apps I can fling/cast whatever you call it to any device on my network so I don’t think it’s a network issue I’m having.

Thanks for building such a great app. I can see it becoming my controller of choice for my home audio system!