Smule is launching a new version of its karaoke sing-along app that takes advantage of the unique processing power of the iPhone 5S to produce effects like the sound of someone singing in a shower.

You're out with friends at karaoke. Your turn is next. But dang, you still don't know what song to sing, and you're not a great singer. What's more, someone just nailed "You Oughta Know" by Alanis ...