It may not be a new KitKat update or anything but it’s still an update for the Xperia Z1 and Xperia Z Ultra. I will quickly break the update down for both devices.
The Xperia Z will now include the Smart Social Cameria Suite which allows you to share media across social networks, improved image-recognition, added AR effects, and so much more that you will have to go and try out for yourself.
On the other hand, you have the Z Ultra with the updated photo-focused featured set that’s also featured in the Z1. It won’t make a giant difference since it don’t feature that incredible 20.7 megapixel rear facing camera and stuck with an 8 megapixel rear facing camera.
A benefit for both devices is that Sony’s native apps are improved which include Messaging, My Xperia, Smart Concept, and even Walkman. As it seems to be closing on 2013 you can expect to see other Xperia devices received the update to Google Android 4.3 Jelly Bean soon.