The dual-tone metal unibody of the M9 is practically identical to that of the M8. The gunmetal gray M9 is just a shade darker than its older sibling; otherwise, you might say these HTCs are twins! Well, almost...

The M9's most noticeable difference from its predecessor is a return to a single rear camera, like the original HTC One. Possibly HTC decided that competing with the 3DS dual camera was a little beneath them.

The M9's secondary metamorphosis was a migrational button shuffle.

With the iPhone 6 and 6 Plus, Apple learned that a top-mounted power button doesn't cut it for a hand-stretching phablet, and moved its power switch to the side. Looks like HTC caught on and followed suit with the M9.

The M9 also replaces the rocker switch of yesteryear with dedicated volume +/- buttons.