Sony today started rolling out Android 4.4 KitKat updates for Xperia Z, Xperia ZL, Xperia ZR and Xperia Tablet Z. The update is going to reach around the world very soon. All these were running Android 4.3 Jelly Bean until now.
some of the functionality you can look forward to includes:
Sony Media apps
Battery Stamina Mode
and the PlayStation app