Assuming all went well, i Tunes 12.1 will sync flawlessly now with i OS 8.1, i OS 8.2, and/or i OS 8.3 (and hopefully all other future i OS versions), and the device will no longer have a bunch of unplayable track names in Music app.
Another two points worth mentioning; i Tunes seems to be less problematic when syncing with a USB cable than with Wi-Fi.
This means that even if you have wi-fi syncing enabled, sometimes just simply plugging the i Phone or i Pad into the computer is a more reliable way to get things to work as they should.
Also, syncing music and movies is often more reliable if you choose to “Manually manage” (that is, syncing manually by dragging and dropping files in i Tunes, rather than relying on the ‘sync’ button, which to me is kind of like the traffic light Customs button you encounter in a Mexican airport in it’s randomized nature).
i Tunes 12 in particular appears to have some annoying issues with syncing that causes a sync and media transfer to get stuck on a step and never complete, sometimes just filling up your device with music and song names that can’t actually play.
Many users have a love or hate relationship with i Tunes, which is required to sync an i Phone, i Pad, or i Pod touch to a Mac or PC (presumably an Apple Watch too).
When i Tunes syncing works as intended, that’s fantastic, but sometimes things don’t work out that way.