Certain songs and playlists put Spotify into full screen mode. This hides the title, and utilities bar (time, battery etc.).
most importantly it gets rid of the queue option. This should be optional like most other special features in the app. If not, allow us to view the queue while in full screen. This is a feature I frequently use and I like to see what songs are coming up next to keep the good music flowing!
I’ve noticed this greatly increases battery usage while in the app too. As well it uses more data as some songs register as a video.