Sony has announced that it is rolling out the Android 4.4.4 update to the Sony Xperia Z, the update brings a range of new features to the Xperia Z.
As well as the Sony Xperia Z, Sony is also rolling out the Android 4.4.4 update to a number of other devices, which include The Sony Xperia Zr, the Sony Xperia ZL and the Sony Xperia Tablet Z.
— Sony Xperia News (@SonyMobileNews) September 9, 2014
The Android 4.4.4 update should be available for the above devices as of now, you can check to see if its is available from the settings menu on your device.
If you receive the Android 4.4.4 update on your Sony Xperia Z, ZL, ZR or Tablet Z, leave a comment below, and let us know any changes you notice, also let us know which region you are in.
Source Xperia Blog