Apparently, the firmware update came with improvements on the Xperia smartphones including new options in the notifications menu for Wi-Fi and Bluetooth. In addition, the Settings menu also got refreshed icons as well as new animations.
In addition to the Xperia Z2 and the Xperia Z3, the Xperia Z2 Tablet and the Xperia Z3 Dual and Xperia Z3 Compact also took on the Android 5.1.1 Lollipop update.
However, the roll out of the update came in stages. Initially, only a few of the listed Xperia devices received the update, but once the release was proven successful, the Android 5.1.1 Lollipop eventually came to the rest of the smartphones and tablets on the list.
While Sony may be working overtime to roll out the Android 5.1.1 Lollipop to many of its Xperia devices, Taiwanese smartphone maker HTC appears to be not in a rush to take on the firmware update for its flagship smartphones.
Accordingly, the current and previous flagship smartphones of the company, the HTC One M9 and the HTC One M8, respectively, have been confirmed to receive the new Android 6.0 Marshmallow that is why the devices will be skipping the Android 5.1.1 Lollipop firmware updates.