Spotify Mini Player Features and Updates :The Android Police website reports that some devices are currently experimenting with the new UI or user interface of Spotify’s Mini Player, and it is expected that all Spotify users will get this new look soon.
Spotify Mini Player Features
The Android Police website has brought down the Progress bar that shows a song being played when compared to its current appearance on Spotify, and also looks slightly different with the Rounded Corners instead of the current Mini Player.
Also, in the Home, Search, and Your Library tabs below the Mini Player, you can see a gradient and transparent background instead of the previous background color.
The website also reports a feature that changes the color of the mini player using the color of the album art of a song
Beebom reports that this is currently only available to a very small number of people as a Server Side Update and if you are already using the latest version of the Spotify App you will probably be able to see this new look.
Source : Android Police Beebom