As Sony already rolled out the Android 5.1.1 Lollipop update to Xperia C3 handsets, reports are now firm that Xperia C4 is also expected to receive Lollipop's final software version through an official download over the air. The update could come shortly after the Android 6.0 Marshmallow debuts on Nexus 5X and Nexus 6P this October 5.

Sony Xperia C4 is ultimately bound for the Android 5.1.1 Lollipop software as it is currently running on Lollipop's first maintenance release. According to new reports, the update should come not later than December 2015 and could be scenting around October as Google releases the LG-made Nexus 5X and Huawei-made Nexus 6P with Android 6.0 Marshmallow out of the box.

The update shall come through an official over-the-air (OTA) release following a string of rollouts to older and mid-range phones. Android 5.1.1 has already been confirmed coming to Xperia Z3, Xperia Z2 and its variants.

Meanwhile, other variants already received the same update in other parts of the world. While the official update has not yet come, custom ROMs have been made available for these devices particularly from well-known developer XDA.

Lollipop's final software version comes with the new LinkedIn app integration to Calendar and Contacts apps, direct access of Wi-Fi and Bluetooth via menu, more Xperia themes to choose from, bug fixes and several other improvements. Here's a quick rundown to new Lollipop's features:

• Camera focus, speed and accuracy improvements in Superior Auto mode
• New Settings menu icons
• Now take pictures from the camera using Sony SmartWatch 3; use the SW3 as a remote shutter button
• Many new features for Xperia in Business, enhancing enterprise support for Xperia
• Calendar agenda in Email - no need to switch apps to check upcoming events
• Instant calendar events - create & share smart events directly from any email
• Improvements to volume and silent mode control, more control of your alerts, simplified and enhanced design

The update shall come in stages. If prompted for the update, just click "Install now" and follow onscreen instructions. To manually check for updates, go to Settings > About phone > System update > Check for updates.

Before installing the Android 5.1.1 version, charge up the phone to at least 50% and make sure storage has enough memory space. Do not forget to back up files since the update will wipe out all data. The device must be connected to a Wi-Fi.