The Repeat icon is available in the Now Playing screen of the BluOS Controller App. It is also available in the footer section of the Play Queue screen in the iOS/Android version of the BluOS Controller App.
Selecting the Repeat icon multiple times toggles between the following three options:
No Repeat 
– Stops playback at the end of the current Play Queue list.
Repeat Play Queue 
– Repeats the playback of the entire Play Queue at the end of the last track.
Repeat Track 
– Repeats the playback of the current track in the Play Queue in a loop.