There's workarounds to make iPhone ringtones. Been using the Sesame Street Yip Yip aliens discovering the phone for right about 10 years straight. Still makes me giggle and answer the phone in a good mood.OMG It's fantastic!
And i realized there are more ringtones on the iphone, i never changed the default since there is no option to add mp3 song!
Here it is if you want it:
Ringtone: https://www.dropbox.com/s/112w0ignyp2ord2/Yip Yip ringtone.m4r?dl=0
SMS tone: https://www.dropbox.com/s/iaj8y4qixeuymke/SMS yip yip.m4r?dl=0
Just drag and drop the song you want into garageband, trim it (a ringtone can only be a couple seconds, I recommend the run-up to the chorus) and export it as a ringtone (m4r). Then sync it via iTunes or whatever the new app on big sir is called.