HTC One will apparently be updating its Android OS to 4.2.2 with HTC UI Sense 5.0, not the rumoured Sense 5.1, and other notably changes
Some changes worth noting in the new OS update are the inclusion of a percentage battery icon enabled under Settings > Power > Show battery level, Android EQS (or Equalizer) controls turned on in the upper right corner of the notification menu, latest HTC update Android Daydream, long press home button operates as menu button, and a new update to Sense 5.0 being the removal of icons from the dock.
The long press home button usually operates as Google Now - the service telling you what's happening in life before you start your day, i.e. what you're doing, where you need to go, and how to get around. The service has recently been introduced on iPhone and iPad.
The HTC One was unveiled earlier this year as the company's new flagship smartphone hosting a bundle of features including a 4.7-inch screen with a full HD resolution, 4MP camera, and two front-facing speakers for stereo sound.
Image & Source: Android Revolution