The arrival of a smart wristband had already been anticipated as a result of HTC's previously announced partnership with US company Under Armour, which supplies smart wearables - including clothing - to the US military.

HTC's Vive headset, however, caught many by surprise. Thanks to a content partnership with Valve - which owns the Steam games platform along with its 65 million users - HTC's headset looks to blow rival Samsung and its Gear VR headset out of the water.

That is saying a lot in these early days of consumer-ready virtual-reality headsets, because the Gear's wow factor is already considerable.

The Vive is a stand-alone device more akin to the Oculus Rift and comes with two controllers.

It features what HTC is calling a "full-room-scale 360-degree solution", with 70 sensors to allow users to walk around - in real space - to inspect objects within the VR experience from every angle.

This was a point of frustration when Fairfax Media tested the Samsung Gear last month: everything felt impressively immersive until you tried to get a better view by craning your neck at an angle, only to find the viewing perspective didn't change.

And with a 90Hz refresh rate, "you're not going to get sick", HTC executive director of global marketing Jeff Gattis said. Motion sickness is often cited as a side-effect of virtual-reality headsets.

"We're confident to say the HTC Vibe will reset the industry standard" for virtual reality, Mr Gattis said.

But, ultimately, it will be content that drives adoption of these early-consumer virtual-reality headsets.

In addition to the landmark Valve partnership, HTC said Vertigo Games, Bossa, Barry, Fireproof, Dovetail Games, Wemo Labs, Google, Steel Wool Games and Owlchemy are already developing beta game content for the device. Google, HBO, Lionsgate and Taiwan's National Palace Museum are working on non-gaming content.

The HTC Grip, meanwhile, is a fairly straight-down-the-line smart wristband.

HTC is pitching the device as a fitness wearable and not a smart watch, although it does have non-fitness functions, including email, message, phone and calendar notifications.

It is GPS-enabled and, unlike some other wearables on the market, is compatible across Android and iOS devices.

Speaking in Barcelona, HTC chief executive Peter Chou said the Under Armour ecosystem would enable access to tailor-made recommendations such as nutrition, training methodologies and injury prevention from fitness experts.

And, of course, fitness data collection, including the requisite daily steps tally and sleep tracking. It does not contain its own heart-rate monitor but can be connected to a monitoring device via Bluetooth.

"Since not every workout is the same, the Grip features multisport modes allowing you to track different types of activities, from walking to running to cycling or even a session in a gym," Mr Chou said.

The Grip has a curved PMOLED display and is being launched in two colours - black with lime or "deep teal" underside - with more colours to follow.

The Grip comes in three sizes but is non-adjustable, which might be a deal breaker for many consumers. The writer has hands and wrists often described by others as "tiny", yet the smallest size of the oblong-shaped Grip felt too tight on the top and bottom of the wrist, and was also difficult to put on, as the latch does not open very wide.

At least one man with average-sized wrists who tried a larger size of the Grip at MWC found it was big enough to go halfway up his forearms.

Its investment in the Grip shows HTC is determined not to miss out on what research firm Gartner is expecting to be a $15.8 billion market by 2020, but with more sophisticated devices - including the Apple Watch - coming on board in 2015, it might have some catching up to do.

Forrester analyst Julie Ask said it was "still early days" when it came to these emerging technologies and few services were doing "micro moments on wearables" and "layering digital on to physical" well.

"A lot of promised [future] experiences will make technology both more pervasive yet invisible in our lives," Ms Ask said.

"It'll just be there helping us, entertaining us and making us more intelligent. Expect technology to be less visible, yet more powerful."

The devices were unveiled alongside the latest iteration of HTC's flagship smartphone, the HTC One M9.

The Grip will be available in selected US stores soon, with pricing and rest-of-world availability yet to be announced.

The developer edition of the Vive will be also available in the US, with the consumer version due later in the year. Prices are also yet to be announced.

The writer travelled to Barcelona as a guest of HTC.

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