The One M9 doesn't offer too much of an upgrade in the specs department besides the Qualcomm Snapdragon 810 chip and revamped cameras, as HTC has instead looked to beat its rivals with high-end design and "personal" software.
The HTC One M9 isn't too dissimilar from its predecessor in terms of design, crafted from the same single piece of aluminium that looks great and makes the handset feel like a premium device.
However, HTC has introduced a new "two-tone" approach. We tried out the gold on silver model, which sees the handset's silvery chassis accompanied by a gloss gold edge, a subtle touch that adds to the all round high-end look.
Perhaps our favourite thing about the One M9's design is its size. The tiny bezel surrounding the device and streamlined feel means it sits comfortably in the palm of the hand, and most people should be able to operate it one handed without any problems.
Rumours had pointed to a QHD display, but HTC has equipped the One M9 with the same display found on last year's model: a 5in Full HD Super LCD.
We remain impressed with the display, which was crisp and vibrant when we reviewed the HTC One M8 last year. However, with higher resolution QHD screens appearing on some of last year's smartphones, such as the LG G3, it would have been good to see HTC go this extra step.
Software and performance
The HTC One M9, unsurprisingly, arrives running Android 5.0 Lollipop, equipping it with all the latest and greatest features of the OS.
Unfortunately, we're not treated to the bare-bones Lollipop interface, as HTC has skinned the One M9 with Sense 7.0, the latest version of its custom software. Many manufacturers have taken a step back from heavy custom skins, but HTC has delved further in, equipping Sense 7.0 with a new feature called Themes.
This enables users of the One M9 to choose from a number of pre-loaded Themes or create their own, changing the colours, icons, fonts and pretty much everything else across the entire interface. This gives the handset a much more personal feel than the iPhone 6, for example, but we wish HTC had opted for a stripped-back interface, much like Motorola offers.
Sense 7.0 also brings a new feature called HTC Home, which places apps on the home screen depending on where you are. If you're at work, for example, your email and calendar apps will be placed at the front of the device, and switched out for Facebook or the onboard TV remote when you arrive home.
In terms of performance, the HTC One M9 packs an octa-core Qualcomm Snapdragon 810 processor. The 64-bit chip comes optimised for Android 5.0, which means that the software is extremely slick and the handset feels smooth to operate throughout.
We haven't yet had the opportunity to benchmark the One M9, but will be sure to do so in our full review.
HTC has placed the main focus on the One M9's front-facing camera, equipping it with a 4MP UltraPixel sensor similar to that found on the rear of last year's One M8.
HTC has paired this with a feature called Dynamic Auto Exposure, which the firm claims will examine images as a human eye would, and adjust them to improve brightness levels, detail and so on.
On first impressions the front-facing camera is better than that on the majority of top-end smartphones, but we still don't think HTC's Ultrapixel technology, which the firm claims makes images lighter and more detailed, lives up to the hype.
With this in mind, it's perhaps a good thing that HTC has decided against putting an Ultrapixel camera on the handset's rear, equipping it instead with a 20.7MP wide-angle sensor complete with dual-LED flash.
We've only used it briefly but we found it a huge improvement on the rear-facing camera on the One M8, probably owing to the lack of Ultrapixel tech.
The One M9 is the only handset besides the Galaxy S6 that comes close to the iPhone in terms of design, boasting a premium feel and shape that's comfortable to use with one hand.
Pair this with an octa-core Snapdragon chip, a 5in HD display and a 20.7MP camera, and the One M9 could be the handset that finally sees HTC catching up with its rivals.
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