HTC has unveiled the long-awaited HTC One M9 smartphone, the successor to the hugely popular HTC One M8, adding support for high-resolution audio and Dolby surround sound processing.

Taking to the stage at a press conference at MWC 2015, the Taiwanese manufacturer unveiled the One M9 flagship phone after months of rumours and internet leaks.

The M9 follows in the footsteps of the One series, with an all-metal unibody design that HTC says melds the best of the One M7 and One M8 together.

The curved, brushed metal back panel from the M8 returns on the new M9, but with the slightly more angular edges of the M7, which HTC says should make it easier to hold.

These edges are also toned in a slightly different colour and finish to the rest of the handset to help them stand out.

The HTC One M9 screen size remains at 5 inches, as before, and stays at full HD resolution rather than going 2K.

HTC has upgraded the processor, however, packing the new octo-core Snapdragon 810 processor. There's 32GB of onboard storage (expandable via microSD) and 3GB of RAM.

MORE: HTC One M9 hands-on review

Features

HTC has always paid attention to the audio on its handsets and the M9 is no different, debuting high-resolution audio support up to 24-bit/192kHz and a new 5.1 Dolby Surround Sound processing mode to its Boomsound equaliser.

Video can be shot for in 4K for the first time too, plus the HTC camera app also gets some new additions, with a whole host of new editing effects alongside the new One Gallery, which pulls images from your phone and online accounts into one place for easy searching by date, location or even face detection.

HTC has rethought the cameras in the HTC One M9, this time placing the previous main snapper, the 4 Ultrapixel lens, on the front of the phone to help with low-light selfies and introduced a 20MP camera on the back. This is no doubt to address criticisms of the M8’s camera in comparison to the competition.

More after the break

Sense 7

HTC is also debuting the new Sense 7 interface on the One M9, which allows you to customise the handset more than ever before. You can now choose pre-installed themes to modify the look and feel of your phone, or customise your own by choosing colours, font, sounds and icon styling.

It’s now also much more tuned in to providing handy location-based help, such as delivering useful apps to your homepage when it recognises you’re in certain places.

BlinkFeed claims to more intelligent than ever too, and able to offer points of interest, news and information on the local area, including restaurant recommendations or perhaps photos you’ve previous taken in the same area.

As for accessories, there's a One M9 Dot View case, as debuted with the M8, the new version now offering more colourways and even some games to play with it, plus there will be an IP68-rated case that will make it waterproof.

The HTC One M9 will be available globally in dual-tone silver and rose gold, single-tone gunmetal grey with matching mirrored edging, single-tone gold with matching mirrored edging and dual-tone gold and pink from mid-March.

You can read our hands-on HTC One M9 review now. Look out for a full review soon.

MORE: Best smartphones to buy in 2015

Two more things...

HTC also launched its first wearable activity tracker, the HTC Grip, and revealed a partnership between HTC and online gaming company Valve to work on virtual reality products.

The HTC Vive VR headset is the first hardware to come from the partnership. Rumours of a Valve VR headset have circulated for some time and it seems the company has joined forces with HTC to work on the hardware.

At today's press conference HTC promised to deliver a consumer VR product by the end of 2015 and launched a new microsite, htcvr.com to promote the company's new virtual reality products (although it's decidedly low on information for now...).

MWC 2015 is expected to showcase new tablets and phones from Samsung and Sony, as well as the just-launched HTC One M9.

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