Android Version 6.0 (also known as Marshmallow or Android M) started rolling out onto Android devices several months ago, with Google's own Nexus devices receiving it first. After that, the tradition is that Android will roll out to devices like Samsung, LG, Motorola, Sony, and now HTC. This is the latest news on Android M Version 6.0 Marshmallow Release Date for HTC One M9, the One M8, and the Desire series for AT&T, Verizon, Sprint, US Cellular, and T-Mobile.
As far as HTC's main flagship phones, the HTC One M9 and the HTC One M8, they are essentially taken care of as far as the upgrade is concerned. In fact, there have been many Retweets from Mo Versi with many satisfied customers of the M8 saying that they are glad to have Marshmallow.
Mo Versi is the VP of Product Management at HTC, and he's usually a good source for HTC Android upgrades. By the way, if you are the user of the HTC One M7, you will not be receiving the upgrade to Android 6.0, as HTC only makes that guarantee for devices that are less than two years old.
We also know from sources like Tech Radar that HTC intends to upgrade more than just its flagships with the HTC One M9+, HTC One E9, HTC One ME, HTC One E8, HTC One M8 EYE, HTC Butterfly 3, HTC Desire 826, HTC Desire 820, and the HTC Desire 816.
According to Android Authority, the new version of Android is rolling out on other HTC devices such as the HTC Desire 816, at least Internationally on dual-SIM versions of the device. The same goes for the International version of the HTC Desire Eye, and Marshmallow has arrived on the Indian HTC One M8 Eye as well.
If you are a user of one of these past flagship phones or any of these previously mentioned International version of phones, check under "Settings" and "System Update" to see if it is available. It is possible that not all United States carriers (US Cellular, Verizon, AT&T, T-Mobile, and Sprint) have received it yet, as some carriers tend to get it before others.
Of course, HTC is not finished giving out its Android upgrades as they intend to unveil their newest smartphone next week. This would be the HTC One M10, or the HTC M10, or the HTC 10. Whatever the name is, HTC is really counting on the #PowerofTen, and you can find out more information on that particular device here until it is formally unveiled on April 12 with a big press event.