This is valid criticism, and shouldn't be getting downvoted just because people disagree.

I'm a huge Rdio fan and love almost all aspects of its design, but (especially on iOS) I regularly get confused as to where I am and how to get back. A few moment's thought (or just fumbling between panels) gets me where I'm going, but there are simply too many almost-the-same-but-actually-different panels sliding around to be intuitive. It's particularly messy when trying to juggle browsing music with a managing a currently playing playlist.