The i1 not only supports iTunes, it is also compatible with many other music apps, including (but not limited to): Spotify, Tidal, and Apple Music. A total of 9 music formats are supported, including AAC (from 8 to 320 kbps), protected AAC files from the iTunes store, Apple Lossless (ALAC), and AIFF. You can be sure that you can listen to your favorite songs, no matter which format they are in.