I am looking for an app that can randomize my ringtones. I am not looking for an app that requires me to jailbreak my phone, though. I would prefer the app to be free.
For Android, there is RandomRing: https://market.android.com/details?id=com.dicren.randomring&hl=en
For the iPhone, I've never managed to find a solution that can be accessed outside of Cydia.