The HTC One M9 is a perfectly lovely phone. Its build is typically impeccable, its Sense skin is easy on the eyes with a few neat tricks, and its front-facing speakers are best in class. But yet, looking back at last year, HTC's 2015 flagship feels like a disappointment.

Criticism varied from complaints about its almost imperceptible design changes to its camera, which fell short of the excellent examples found in the Samsung Galaxy S6 and LG G4. That was then though, and a new year is upon us - one with plenty of smartphone promise.

The Galaxy S7 and Galaxy S7 Edge have already impressed us, replacing their predecessors atop our list of the best smartphones in the world right now, and the LG G5 had a very promising debut at MWC 2016.

But HTC's new One M successor, reportedly just called the HTC 10 this time around, could be the dark horse to disrupt those powerhouse phones after a less than spectacular showing the last time around. Much has already leaked about the handset - here's what we know.

2K Club

None of HTC's previous M series flagships managed to dip their toes in the 2K resolution waters, but all the rumours point to the M10 taking the plunge.

According to leaked specs from King Leaker @evleaks, the M10 will have a slightly larger 5.1in, 2K display, bringing it in line with its main Samsung, Sony and LG rivals.

Interestingly, the display will also apparently be an AMOLED affair - another first for an M series flagship.

The Samsung Galaxy S6's Super AMOLED 2K screen is widely regarded as one of the best smartphone screens around at the moment, so if HTC can match it for colour reproduction and sharpness, then it could be onto a winner.

Although the display will be slightly larger at 5.1 inches, we're hoping that the bezel reduction will make it more manageable for smaller handed users.

Snap happy

HTC has never quite managed to nail the camera on its past few flagships. The M9 scored rather poorly in our 2015 smartphone camera supertest, and was easily outclassed by the superb cameras found on the Galaxy S6 and G4.

HTC has experimented with UltraPixel cameras in the past, with decent, if not spectacular results. What let it down however, was the resolution, with the One M8's 4MP affair taking criticism for the low megapixel count. That looks set to change in the M10 though, with a 12MP UltraPixel snapper apparently taking over

The benefit of 'UltraPixels', as HTC calls them, comes from their larger size. Bigger pixels suck in more light, which means more detail in low light conditions.

If the specs are true and we really are looking at a 12MP sensor, then colour us happy. If HTC can nail the post-processing, we could be looking at sharp, detailed photos that can be cropped into without encountering fuzzy noise.

More powerful

Surprise surprise - the One M10 will be HTC's most powerful phone yet.

The handset is expected to arrive with Qualcomm's latest, most powerful processor, the Snapdragon 820, churning away under the hood.

Coupled with an expected 4GB of RAM, we expect nothing less than perfect performance from Android 6.0 Marshmallow, even with a new version of HTC Sense running on top.

The proof will be in the pudding, of course, and benchmark numbers don't necessarily mean real world performance is slick and smooth. Again, we'll have to wait for our full review to see how Qualcomm's silicon handles the real world.

Price and release date

All the latest rumours point to HTC avoiding Mobile World Congress as the launchpad for the M10. Instead, the company will apparently hold its own launch event in London, on 11 April, ensuring that the M10 gets all the limelight.

The One M9 hit shelves a month after its March reveal last year, and if HTC follows the same pattern, we expect to see the One M10 in pockets in May.

We'll be bringing you all of the official M10 news from its expected launch event, so stay tuned.