The new Retina Display Jamzu updates are both available in the App Store.
Working hard on getting Jamzu 1.60, with multiplayer online, ready very soon! Beta testing starts next week.
Also working on the iPad version of Jamzu, which will be free with In App Purchase.
Jamzu 1.50 is in the App Store:
Jamzu Lite 1.1 is in the App Store: