The problem is, you DON'T NEED Ringdroid, or any other app. The ability to use music (mp3, AAC, etc) is BUILT-IN. If you're running ICS, just open MyGallery, go to the song you want to use, press the "Menu" button, and select "Use as ringtone'. If you're running JB, copy the song(s) from whatever folder they're in, and paste them into the "Ringtones" folder on the phone (make sure it's the "Ringtones" folder on the phone, NOT the folder on your SD card). Anyone who thinks/believes they need to install an additional app in order to do this might want to have their head examined.