The KeyOne is BlackBerry's latest attempt to haul itself back from the brink of destruction - and it's a pretty good attempt too.

The first handset made in partnership with Chinese manufacturer TCL, the KeyOne - formerly known by the codename 'Mercury' - has almost everything a BlackBerry addict would want from a phone in 2017.

That means a hardware keyboard, premium build, decent specs and Android 7 rather than BlackBerry's own OS.

I had a play around with it at MWC 2017, and came away liking what I saw.

It's all about the keyboard

As its name might suggest, the most notable thing about the KeyOne is its hardware keyboard.

It shouldn't really be news that it has one - surely a BlackBerry's defining feature is its keyboard? - but then again, BlackBerry's released several phones recently without one. Anyway, it returns here, and for those of you that crave a physical keyboard, it'll be a delight.

It's not exactly spacious - I did sometimes end up pressing two keys at once - but it's big enough that I think I'd get used to it, and the keys themselves have a nice clickiness to them. It's somehow more satisfying than using a touchscreen: whereas I'd never want to write a 2000-word review on an iPhone, on a BlackBerry it might be possible.

The smart features are a bonus, too. The phone flashes up suggestions as you type, and you can then swipe upwards to select the one you want. I got the hang of it no time, and the KeyOne is unnervingly good at predicting what you're going to say next. Alright so you can download plenty of apps which do much the same thing, but BlackBerry's version is among the best.

The ability to set shortcuts is also handy - holding down E to go to email, for instance. I didn't have time to really experiment much with this feature, but I can see it being particularly useful for more advanced shortcuts such as jumping straight into composing a text message to a specific person.

You can also swipe around the keyboard to navigate within apps, although my attempts mostly sent me in entirely unexpected directions. Again, I think I'd get used to it in time.

The pros and cons of a 3:2 screen

The keyboard defines the KeyOne to the extent that the screen has to be a weird shape to accommodate it.

Yes, in order to fit in a full QWERTY without making the phone about a foot long, TCL had to squash down the display. As a result, it has an odd 1620 x 1080 resolution and 3:2 aspect ratio.

This has both good and bad consequences.

On the plus side, web pages and apps look great when you're typing in them - the KeyOne's physical keyboard takes up less room than the pop-up ones you get on solely touchscreen phones, meaning less of the page gets obscured by the keys.

It's particularly effective when using the split-screen feature that arrived with Android 7, because on any other phone almost all of one app gets lost behind the letters as you type in the other. On the KeyOne, though, both screens are fully visible as you're typing.

The downside to it is that most apps and games aren't designed to be viewed on a 3:2 screen. Stick on a YouTube video, as I did in the photo above, and you'll get black bars above and below the content.

Obviously you also get a smaller screen overall too - it's 4.5in, where even an iPhone now has a 4.7in display. The full HD resolution is nothing to shout home about either, given that QHD screens are now the norm at this price.

Still, colours are good, and viewing angles decent - although given that I didn't get the chance to test it in bright sunlight, my opinion might change on that front.

A nice bit of kit

The KeyOne's build really impressed me. It feels sturdy, thanks to the metal frame, but surprisingly light with it. The dimpled back serves two purposes - it feels nice in the hand, but also gives you a bit more grip. It's quite thick compared to most modern flagships, but not so much that it's unwieldy.

On the right side of the phone there's a volume rocker plus what you expect to be the power button - but which is actually the KeyOne's customisable Convenience key. You can set this to do almost anything, such as mute the volume, or dial a specific person.

It falls nicely under the thumb when you hold the phone, but whether it's really needed is a different matter, especially given how many shortcuts you get via the keyboard. I also know I'd find myself pressing it by accident when I meant to press the power button, which instead sits on the left hand side of the device. 

There's USB-C charging down the bottom, and a headphone socket up top, while the space bar on the keyboard doubles as the fingerprint scanner.

Design-wise, it looks like a BlackBerry; it couldn't really look like anything else with that keyboard down the bottom. Now call me shallow, but I don't want my phone to look like a BlackBerry, because people will think I'm using a phone from 2010. That's not the KeyOne's fault, but it is BlackBerry's (or TCL's) problem to deal with.

Then again, given that I only wear a suit for weddings and funerals the KeyOne probably isn't aimed at me. The people who it is aimed at - businessy types who wear Bluetooth headsets and talk loudly - will probably like the look of this phone.

Software - the best of both worlds

The other thing businessy types will like here is the OS. They'll like the fact that it runs Android 7.1 and that they'll be able to download all the apps Samsung or LG owners can - and they'll also like the fact that the KeyOne includes the BlackBerry Hub messaging system and DTEK security software.

I wasn't able to really put either of these to the test - a launch event isn't really the place to be downloading potentially unsafe apps or setting up dozens of different email accounts. However we've tested these features before in the BlackBerry Priv and DTEK50 phones, and generally found them to be nice additions.

Other than that, what you have here is a fairly stock Android Nougat experience with a few BlackBerry 'enhancements'. There are some extra shortcuts, for instance the ability to swipe around on the keyboard and bring up apps, and you can add widgets to apps by long-pressing them. Nothing truly essential, then, but nothing to complain about either.

This phone should take a pretty picture

TCL has done the sensible thing with the KeyOne's camera, and kitted it out with a tried-and-tested sensor from another phone. The sensor is the Sony IMX378 and as I'm sure you all know from its name alone, it's the one you'd find inside the Google Pixel.

This is a good thing, because the Pixel takes very nice photos, and the KeyOne therefore should too. You get 12MP to play with, plus speedy phase detection autofocus. Round the front there's an 8MP camera which should come in handy for videoconferencing or snapping cheeky selfies when the boss isn't looking.

Unfortunately, you'll have to wait until we review the phone fully for a proper verdict on its photographic abilities, because the launch event venue really wasn't the place to test it out. It seemed to cope well enough with the extremely dim lighting inside, still finding and snapping on to targets, but that's about all I can say about it right now.

BlackBerry KeyOne initial verdict

Outside of those features the KeyOne is an upper-mid-range Android. You get a Qualcomm Snapdragon 625 processor inside it, which is smack bang in the middle of the range and optimised for battery life rather than speed. You get 3GB of RAM and 32GB of built-in storage, plus up to 2TB more via microSD. And you get a big 3505mAh battery with fast-charging.

Its price, however, is closer to the top end of things: US$549 (RM2440) makes it more expensive than all but the very flagship devices.

For that reason, I can't see anyone outside of a BlackBerry devotee being swayed by it. It's a really nice phone in lots of ways, with a lovely build and plenty of sensible features, but whether you'd get one over an iPhone or a Samsung Galaxy S7 would depend almost entirely on whether you wanted that keyboard. If that sounds like you, then you're probably going to love the KeyOne.

We'll have a full review as soon as we can - and don't forget to keep up with all of our MWC 2017 coverage here.