Please optimize the Spotify app for the iPhone X.
There are black bars at the top and bottom in the app, and because of that, the app doesn't look very great on the device. I'm sure that it's possible to "fix" this in the next few days/weeks so that the app is looking great on all devices again.
Updated on 2017-12-08
This has now been implemented in the latest verison of Spotify. If you can't see this update, we'd recommend following the steps here.
Thanks for the reports!