Effective Living > Music Summary. Yusuf Islam (Cat Stevens) became popular in the United States for his music focusing on transcendence and peace. The song by Cat Stevens featured on a recent T-Mobile commercial (below) is If You Want to Sing Out, Sing Out. The lyrics for this song are provided further down on this page. More… Continue reading Cat Stevens Yusuf Islam Music Song If You Want to Sing Out Sing Out featured on T-Mobile Commercial Listen Now Lyrics