When using Android 4.4 Kitkat (vanilla Android), the "previous track" and "skip track" buttons on the lockscreen sometimes disappears.
You have to pause and then play again (or turn the screen off) in order for them to reappear. This happens often when you skip songs.
This is very common, as many users have mentioned it in this thread http://community.spotify.com/t5/Help-Android/Android-4-4-Spotify-doesnt-load-images/td-p/576494)
Solved! Go to Solution.
This is a known issue on Android 4.4 KitKat. I know the team is aware of it and are currently working on a fix (album art issue has been fixed, but has not yet been pushed to play as I believe they hope to push both fixes out in one go).