Android 5.1 Lollipop Update on HTC One M8, M7, Nexus 4, 5, Xperia Z3, Xperia Z2

The final version of Android 5.0 Lollipop was unveiled only last October 2014, and as of the moment, the Android 5.0.1 and 5.0.2 Lollipop updates have rolled out to many of the Nexus phones, but both updates to the original 5.0 Lollipop still suffer from bugs and other problems.

Lollipop is a rather large update, bringing back the silent mode that is missing from Android 5.0, improving RAM management, system stability and battery management, as well as fixing sudden app closures, Wi-Fi problems and sound problems.

It's important to note the difference between Android 5.1 and the Android 5.0.1 update that rolled out to Nexus devices in December. (The Nexus 7 2012 and cellular versions of the Nexus 7 didn't get 5.0.1, but have recently received 5.0.2.) The 5.0.1 Lollipop update is a collection of bug fixes that we recommend installing.

Sources told Android Pit that the 5.1 update for other phone units will be available sometime in the first quarter of the new year, citing two trusted and completely separate sources.

Looking back, Google launched Android 4.4 KitKat last September and then showed off Android L at its I/O 2014 developer conference before officially announcing its final name and version number on 15 October.

As for the release date for different mobile devices, Sony has confirmed that it will bring Android 5.0 Lollipop to the entire Xperia Z range which is quite impressive as some are pretty outdated now. Upgrades will start with the core Xperia Z3 and Xperia Z2 series in early 2015.

The HTC One M8 or M7 will have its update within 90 days of getting the final version of Android L from Google so you an estimate of it being available by February 2015 is realistic. All the other 'One' smartphones will get the update, but it will be after those first two devices.

While there rumors indicating that the 5.1 Lollipop will first roll out to the Nexus 4 and Nexus 5, they are not confirmed yet, but new details should be emerging in the coming days and weeks.