For more information on Cesium's features, check out the User Guide
Does Cesium work with iCloud?
Absolutely! Cesium supports playback of any track in your iTunes Library, including purchased music in the Cloud and iTunes Match tracks.
What about Apple Music?
Any Apple Music tracks that have been added to "My Music" can be played using Cesium, whether they are stored on your device or in the Cloud.
What's the deal with star ratings?
A popular question. I've addressed this in more depth here, but in a nutshell: if you still sync your music to iTunes the old fashioned way (via cord or WiFi), then Cesium is going to work just perfectly for you. Unfortunately, third party apps cannot modify the iCloud Music Library (for now), so if you need ratings to sync across multiple devices via iCloud then Siri is the only option :(
Will Cesium update my play counts?
Yes. Cesium uses the same iOS system player that the stock music app uses. Play counts, playback position and ratings will all behave exactly the same way.
Can I view the lyrics I added in iTunes?
Yes! Cesium respects the "Lyrics" tag as entered in iTunes. You can view lyrics by tapping the Album Artwork in the Now Playing pane or in the Track Details view.
Can I side load my music, or directly drag files into Cesium?
Can Cesium play other formats like FLAC?
Cesium pulls its data from the iTunes library and is currently requires music files be synced via iTunes (or third party replacement that updates the iTunes Library database) and is only currently compatible with music formats supported by iTunes.
How do I play or shuffle all the songs by a specific artist?
Collection Control! Simply swipe left-to-right on any track grouping (artist, album, playlist, genre, etc.) to reveal controls that allow you to play or shuffle only the tracks in that group.
Does Cesium have EQ or Crossfade features?
At the moment Apple APIs do not allow support for both audio processing (like EQ or crossfade) and playback of DRM files, including Apple Music. So at the moment Cesium does not have dedicated EQ, but it is fully compatible with the default EQ options found in in the iOS Music Settings.
Can you add a "Create Playlist" feature?
Third party apps cannot write to the iTunes Library file, which means that Cesium can not add, delete or modify iTunes playlists.
I have a suggestion, or think I found a bug. What can I do?
Why the name "Cesium?"
It's an anagram for m-u-s-i-c. OK, technically e-music, but "Csium" was really stretching it.