toqueparacelular

Pi Music Player is a music app that has some ringtone capabilities as well at https://toqueparacelular.com/. The app has a five-band equalizer, metadata support, themes, and a beautiful user interface. It also has a ringtone cutter function that lets you take any track in your library and turn it into a ringtone or notification tone.

GarageBand for iOS is another iPhone ringtone maker that lets you trim any song into 30 seconds or less. It's a good way to create a ringtone from your favorite song, but it can be a little frustrating.