They promised a 90 day window from receiving the source code from Google before they would roll out the update to the masses, and HTC has pretty much delivered on the perfect timeslot the much awaited Android 5.0 Lollipop update for the HTC M8. The update is now rolling out for those in India after those in South Eastern Asia zone had confirmed the update was rolling out in countries like Malaysia and Singapore earlier last week. It is worth noting that the update is around 560 MB much compressed as compared to the 700 Mb+ version that was being rolled out in other regions of Asia.
The new update brings Lollipop to HTC M8 and other than the new Android version, there is very little in terms of changes in Sense 6.0 for us to take note. You do have a new lockscreen and the status bar coloring effect based on the application header color. You also have the new Lollipop animations and the new app recent menu for quick multitasking. It is being reported that the battery performance of the device has deteriorated post the Lollipop update, though we are yet to check this out.
— Arpit (@RedArpit) February 2, 2015
In order to get the update, you need to connect your M8 to WiFi and simply check for updates in Settings-> About phone.