The M9 comes packed in a two-tone color scheme and a lighter body.
The main rumors about a more powerful processor and a 20 megapixel sensor were confirmed.
The device is powered by a 64-bit octa-core Snapdragon 810 processor and boasts 3GB of RAM and 32GB of internal storage, expandable via a MicroSD reader (up to 128 GB supported).
The smartphone is equipped with a unibody aluminum shell and 5-inch 1080p Full HD display.
At the back of the phone, a square camera cut-out carries a 20-megapixel sensor and the 2840 mAh battery ensures over 21 hours of talking on 3G.
The new HTC device will have Android Lollipop, the latest mobile operating system from Google.