If you have a Sony Xperia Z1, Xperia Z1 Compact or Xperia Z Ultra, it might be time to check for updates, as Android 4.4 KitKat is currently rolling out.Sony has confirmed the rollout on its official blog, adding that it has worked on one or two of its own tweaks as part of the rollout. First and foremost though, this is about KitKat, so expect changes with your phone dialler, an enhanced Hangouts app, voice control via 'Ok Google', native cloud printing, changes to notification bars and lock screen album art, not to mention a more efficient operating system, thanks to better use of your on-board memory.On top of that, Sony has altered Status Bar and Quick Settings, which are now 'more intuitive and customisable' so you only get the notifications you really need. The user interface has also been changed to something like the ones on the PlayStation 4 - so with sleek launch animations and live wallpaper across the lock and home screens.In addition, Sony’s entire native app portfolio has been upgraded to the latest versions, including Messaging, MyXperia, Smart Connect, Small apps, TrackID, TrackID TV, Sony Select and Smart Social Camera. Sony is also altering its Walkman section, adding Sony Entertainment Network cloud service integration, along with Sony Entertainment Network and PlayMemories integration.All good? Right, now here's the bad news. Sony is being particularly vague about timings, so we really don't know when it will hit UK phones. When it does, the first will almost certainly be SIM-free handsets, followed by contract phones further down the line. Sorry we can't be more clear, that's all we have.Once that rollout is finished, Sony plans for the Xperia Z, Xperia ZL, Xperia Tablet Z and Xperia ZR to receive Android 4.4 KitKat. That's from the middle of the second quarter, so this update should be done and dusted completely by around May.