Converting an audio track to MP3 on the Mac is dead easy. Just open it with iTunes, and choose the File > Convert option from the menu bar. On iOS, though, there’s no native way to do this. There are lots of shonky-looking apps in the App Store that offer to create MP3s for you, but it’s likely that you already have the answer installed on your iPhone or iPad.
That’s right. Apple’s own WorkFlow app can quickly and easily convert any audio (or video) file to MP3.