I wasn't even sure whether the Spotify app was updated for iOS7 until I looked it up. To put it bluntly, while the app is functional enough (even if it still lacks basic features like being able to rearrange the position of playlists), it looks straight up ugly. Ugly to the point that it makes me consider switching to a competing app for example.
Take rdio for example, their app is drop dead gorgeous.
Compared to Spotify,
A redesign more in line with iOS7 design philosphies would be much welcomed. If you want ideas on how it could look, look at some of mockups available online (http://xooplate.com/templates/details/14889-new-flat-spotify-ios-app-remake-set-psd & http://thezinx.com/2013/12/29/spotify-ios-7-redesign-concept.html)