Android 5.1 was just released to manufacturers earlier this year, but it’s already coming to devices such as the Nexus 6 and will be pre-installed on flagships like the LG G4. It will take a few months for manufacturers to update their phones to the software, but HTC may already have a timeline of when we can expect it for the One M8.
@JKMcCloskey Hey James, the HTC One M8 will have a Software Update for Android Version 5.1 and Sense 7 in August 2015 🙂
— HTC UK (@HTC_UK) April 29, 2015
Of course, it is still much too early to tell when the update might come out, since HTC missed their original target date they had for giving Android 5.0 to customers. And since this is HTC’s UK account, there’s no telling when other countries might get their updates for Android 5.1