HTC confirmed today that the One M9 will be officially introduced on March 1st at the Mobile World Congress 2015 in Barcelona. The smartphone is rumored to come with a 5-inch fullHD display, a Snapdragon 810 chip, and a 20.7MP primary camera.
http://www.notebookcheck.net/HTC-teases-the-One-M9-for-March-1st-announcement.136648.0.html