From the Store description:
Take your Zumba® Fitness workout wherever you go with the revolutionary new motion-based Zumba® Dance app! Zumba® Dance is the first app with full routines and that can provide feedback and encouragement. Let loose with contagious choreography through Zumba’s signature “exercise in disguise” program on-the-go or at home. Follow along as superstar Zumba instructors, Beto Perez, Gina Grant, and Kass Martin, guide you through each heart-pounding class. Let the music move you with three hours of available routines! Shake it up with chart-topping hits, from LMFAO, Pitbull, Tiesto, Kat Deluna, and Sean Paul, in addition to contagious Zumba original tracks.
Here's Zumba Dance in action:
The front camera of your smartphone, suitably propped up, gives visual feedback on how closely (or how terribly) you're following the on-screen animated guide.
With a 'pumping' soundtrack, you'll want to use Bluetooth headphones or wire your phone up to some decent speakers for best workout effect....
Zumba Dance keeps track of your daily and weekly efforts....
...along with estimating the number of calories burned, based on your sex and size.
You can buy the initial 20 minute workout version of Zumba Dance here in the Store. You can then 'maximize your workout by purchasing up to 3 pre-programmed 60-minute classes or by creating your own playlist of previously purchased routines with the custom class feature'. It's a little odd to see a paid application also include further in-app purchases, but in fairness there's commercial music content in here and that has to be properly licensed and accounted for.
[PS. I do wonder if Zumba Dance can be hooked up via DLNA 'Play to' or similar, to a home TV and stereo system. Anyone tried this?]