This announcement came from Jeff Gordon, HTC's Senior Global Online Communications Manager. And he added, HTC will add more device with Android M in the upcoming days.
Moreover, the Android M will bring a host of improvements to the platform. They include granular app permissions, custom Chrome tabs, app links, and Android Pay among others.
Moving on to the specs of One M9, comes packed with 5-inch display, 1.5GHz Octa-core Qualcomm Snapdragon 810, 3GB RAM, 32GB internal memory, 128GB expandable memory, 20MP rear camera, 4 Ultra-Pixel, Android 5.0 on top of Sense 7.0 and powered by a 2840mAh battery.
On the other side, One M9+, comes packed with 5.2-inch display, 2.2GHz Octa-core MediaTek MT6795T, 3GB RAM, 32GB built-in memory, 20MP rear camera, Android 5.0.2, 2840mAh battery.