Zikera has Groove: Smart Music Player (iTunes Link) for the iPhone and iPod Touch in the iTunes App Store for FREE (regularly $3.99) for a limited time.

Don’t know what to listen to? With Groove, find the perfect playlist for any occasion in just a few taps. Groove studies your listening habits and creates a wide variety of instant mixes like your own personal DJ. You’ll never have to manually create a playlist again.