Google's latest Android 6.0 Marshmallow operating system (OS) first arrived at HTC via the new One A9 handset. However, the first model to be updated to the Marshmallow OS is, in fact, the Google Play Edition (GPE) of the HTC One M8 flagship, which has just been announced by Mo Versi, the company's vice president for product management.

It is important to note that this GPE version is not the regular One M8 flagship released by Taiwan-based device maker last year. A Google Play edition model is a handset that runs the search giant's stock Android. It means that it does not carry the company's own Sense UI, which is layered on top of the stock Android OS in most HTC models.

GPE models are usually among the first to receive upgrades whenever new OS versions are released. The updates are handled by Google itself and are sent out to original equipment manufacturers (OEM).

Late last month, Versi mentioned that there had been a slight delay in rolling out the over-the-air (OTA) Marshmallow update. Back then, he said that the Technical Approval needed to distribute the new Android build was days away from being received.

The new OS promises to deliver improved system stability and security, along with battery life enhancements courtesy of the new power management system called Doze Mode. This feature will be able to detect when a handset is not being used and will automatically begin disabling applications that would typically be running and updating in the background.

Another notable feature is "Google Now on Tap" which works by letting Google give users contextual search results based on what they are looking at on their device's display. Other improvements include native support for fingerprint sensors and the new individual permissions request for mobile apps.

In September, the company shared a list showing which models it is planning to upgrade to Android 6.0 soon but did not disclose any roll out date. Tech site GSM Arena, meanwhile, posted its list of handsets expected to receive the much-awaited OS. The site said that the company will send out the Marshmallow update before this year ends to the following models: One M9, One M9 Plus, One E9, One E9 Plus, One M8, and One E8.

For those who own an HTC One M8 GPE model, they can navigate to the Settings app to start checking for the OTA update. It will be rolled out in phases, so not all devices will receive the OS at the same time. The Marshmallow upgrade has a 450MB file size, so users are advised to connect to a WiFi network first and make sure that their battery level is more than 50% before installing the upgrade. Users who have not received the update can otherwise download the OTA file from Google here and install it manually.