Android 5.1 firmware for the HTC One M9 spotted, custom ROM ensues

If you don't want to wait for the update to hit your handset, you can install this custom ROM, but you need to be rooted, with recovery installed, and so on. What the latest Android will bring to the M9, besides the obligatory bug squashing, is a new native display color management, and multi-user support. The DND mode, and alarm control settings have found a comfortable placement next to the volume slider in the notification bar, too. Head down to the source link if you are interested in the instructions how to install the Maximus HD custom Android 5.1 ROM for your HTC One M9.

source: LlabTooFeR via AndroidAuthority