This update is available on the PC application and there is no announcement about the OTA update. This update comes in 1GB of size and released in batches.
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On the other hand, Lollipop update comes with new material design which offers a bold, colorful and responsive UI, refreshing notification system.
It will also allow the users to see the notification in the lock screen and they will get displayed like banners on the top of the screen.
Additionally, there is a do-not-disturb feature added to the notification bar. This update also contains battery optimization, which includes battery saver mode, job scheduling and a new developer tool called Battery Historian which tracks the battery consumption by an application.
Reiterating the specifications of Xperia Z2, it sports a 5.2-inch display with a resolution of 1080x1920 and comes packed with 2.3GHz processor alongside 3GB RAM, 16GB internal memory, 128GB expandable memory, 20.7MP rear camera, 2.2MP front camera, Android 4.4 KitKat on top of Xperia UI and powered by 3200mAh battery.