Android 6.0 Marshmallow update was expected to officially roll out to HTC One M8 smartphones in December 2015 but to a select versions only. Accordingly, Marshmallow is going in full swing to the devices across the globe in the first quarter of 2016 along with the much-anticipated Sense 7.0 user interface.

HTC One M8 handsets are confirmed to receive the official over-the-air (OTA) update of Android 6.0 Marshmallow anytime in January as beta tests had been initiated in December 2015. The device currently is expected done with its final testing stage.

Most HTC devices were last updated to Android 5.1 Lollipop last month, skipping 5.1.1 version. Meanwhile, One A9 is HTC's sole smartphone to sport the Android 6.0 Marshmallow for now as it came out of the box with it.

Android 6.0 Marshmallow update comes with Sense 7.0 user interface to most of its smartphones. Sense 7.0 is HTC's own UI that offers more customized animations for users. Along with the user interface, Marshmallow is slated to come with a new and update set of emojis. Emojis made noise in the tech world these days to its impressive tweaks and additions.

The upgrade will bring in several new features and improvements to overall system performance. This includes power saver Doze, improved apps permissions, more intuitive Google Now with Now on Tap, support for fingerprint sensor, USB Type-C and Android Pay which has more mobile payment methods available, and more.

One M8 is the first device to receive Marshmallow over the air. While the official update has not completely come out yet, custom ROMs have been made available to the device to make a first experience of the biggest build in Android history.

Android 6.0 is also confirmed to be released to HTC One M9+, One M8 EYE, One M8s, One M8 Google Play Edition, One ME, One M7 DS, One E9, One E9+, One E8, Desire EYE, Desire 826, Desire 820, Desire 816 and Desire 816 G.