TL;DR: I would love a queue option in the iOS app.
I often use my ipad to watch (more like listen to) comedies like Big Bang Theory or Scrubs while I'm working in the garage or in the yard or something. It works great with the minor inconvenience of having no way to create a playlist like you can in the Plex Media Center client.
And now that I think about how I use it in the yard, I would love to be able to lock the screen and just hear the audio continue playing if I choose.
