I'm making an iOS app in which I'd like to allow the user to save an audio file (a specific file that the app uses internally, not just any arbitrary audio file) to their music library so they can play it from other apps on the device. Ideally I'd like to save a sound directly to the users music library, but it seems from other similar questions that this is not possible. File sharing with iTunes seems to be the next best solution.
Is there anything about using the iTunes file sharing option for saving audio in this way that violates the app store terms?
Is this the path of least friction for the user, or is there another way to achieve this that I'm missing?