Is there a way of getting music on the iphone 4s without using itunes?

For example can you connect to Wi-Fi and get songs off the imternet on the iphone? Or is the only way through a usb cable.

Download idownloader from app store then use a website called m.fivito.com in the idownloader browser section and covert any video from youtube to mp3 very easy. Just copy and paste from safari to the fivito website