The back button on the album view seems to have disappeared on the iPhone app? If I go an artist, click on an album, then play a track, I have the down arrow to drop the play screen back to the album, but there's no back button to navigate back to the artist page.
We've reached out to our tech team on this one.
We can confirm that right now, this is expected behaviour.
Rest assured however we've passed your feedback about this directly on. We appreciate you sharing your thoughts.
Apologies for any confusion, and let us know if you have any other questions in the future.