At first glance the M9 looks extremely to the M8 which is not a bad thing, but a lot of people are getting upset of HTC for only making incremental changes to their flagships, The M9 has dropped the dual camera setup, to a single camera set up. It no longer has the Ultra-Pixel sensor, it is now a 20 MP rear-facing camera which is a good thing but I find the very washed out. I had much better results on the iPhone 6 and Galaxy S6 and the M9 does get really hot, especially after you use it for a while