kensington314 wrote
However, when I try to put songs from my library onto my iPhone using Banshee, it doesn't work. The songs seem to be on the iPhone as files: when I disconnect my music library I can play the songs through Banshee with my iPhone still attached.
But the songs are not there in the iTunes interface on my iPhone, and I can find no way to locate or play them after disconnecting from my computer.
I too have had this problem, and after a good deal of research I found that libimobiledevice (the library that all Linux software uses to interact with iOS devices) has not supported writing to the modern databases that iOS devices use to handle music. As far as I can tell, it just treats the device as a USB Mass Storage Device with songs accessible from computers. There may be a method to access from a jailbroken phone, but jailbreaking is becoming increasingly complicated as jailbreakers often don't hack the latest iOS versions and you cannot restore to prior firmware revisions once updated outside of a tiny window. The only method I have found to manage my iPhone's music with the native Music app is to dual boot Windows and install iTunes.