The slide gesture that is used to open the iOS 7 Control Center can cause the spotify app to advance to the next song when viewing art work in full-screen mode. Consider the following scenario on the iPad:
Listen to Spotify Radio while viewing album artwork in full screen mode.
Hear a song you like.
Try to increase the volume by first attempting to open the Control Center (i.e.. slide your finger up from the bottom of the screen).
Rather than the control center opening, Spotify Radio will often advance to the next song (exactly what you don't want to happen when you hear a song you like). This is particularly annoying because the Back button does not work on Spotify Radio (another issue).