The great thing about this app is that there's no ads or nagware. It's free and all it does is make a whip sound. So far it's been great fun. It's a completely unproductive app which I highly recommend. I tried several other whip apps. Some had cool features like machine gun sounds, but they all had varying degrees of overbearing crap. This app is as minimalist as you can get. Just you and your whip.
Use is simple and intuitive: hold your phone like a whip and make a whipping motion.