That means you can use the entire 8-inch display even when the phone is closed. Unlike the Galaxy Fold, there is no internal Mate X display.
By folding backwards as it does, that big screen is essentially split in half, giving you a 6.6-inch display in its regular, "closed" phone format, outsizing all but the biggest phablet giants. (You get full use of the screen only when you unfold the phone.)
As a result, videos and photos look great, particularly because there's no notch interrupting the view.
Having a big outer screen in "phone mode" makes it much more usable than the closed Galaxy Fold. In my several months with the Fold, I've found its 4.6-inch outer screen to be so narrow that typing on it can be extremely difficult. As a result, I almost always use it in its large, folded-out tablet mode.
The Mate X's design is comfortable to use and while it's wider than the Fold, it's much thinner in its closed form, so it sits in my jeans pocket more easily and didn't feel at all awkward.
The downside? By bending outwards, the rear screen is permanently exposed to the world, or to potentially damaging keys and coins in your pocket.
The OLED display itself is bright, vibrant, pin-sharp and even under the bright lights of my hotel room -- and later, under the admittedly gray sky of Paris -- I didn't struggle to read what was on screen.
Watching videos in phone mode is great, but it's when you fold it out into its full 8 inches that those videos become significantly more immersive. I really loved checking out the images I shot on my day out in the city on that big display.
To allow it to bend, the display is covered in plastic, not glass (as are all of today's foldable phones) and, like we've seen on the Galaxy Fold, there are some noticeable ripples on the screen's surface when it lays flat.
But they're best described as "ripples" rather than the more pronounced "crease" on the Fold. This is likely due to the fact that the screen doesn't bend at such a sharp angle, thereby causing less of a crease in the display material.
In my extended hands-on throughout the day, I rarely noticed these ripples and never found them to be a distraction.
In addition, the folding hinge is a bit stiff. Bending it backwards from its tablet mode feels like you're having to force it more than it really wants, and on my first few attempts I wasn't sure if I was doing it properly.
The cameras are housed in a vertical side-bar, which I found to be a handy gripping point when unfolded in tablet mode (when closed, the phone folds back, sitting flush against this sidebar).
It also means the cameras don't interrupt the display with notches, not even for selfies, as you simply turn the phone over and take those with the main camera.
Having used the cameras extensively throughout my time with the smartphone, I'm pretty pleased with the results, particularly the portrait mode, which gave an extremely accurate bokeh around my willing subject.
Other specs are pretty much in line with what you'd expect from any top-end smartphone. It runs Huawei's latest Kirin 980 octacore processor, has a 4,500-mAh battery with all-day battery life, 512GB of internal storage and 8GB of RAM.
Having spent all day with the Mate X, I'm confident in saying that this is my favourite foldable phone I've used so far. My time with it has left me extremely excited about what we'll see from folding devices in the years to come.
For more information, check out CNET's Huawei Mate X hands-on.
Click or swipe through for more photos of the Huawei Mate X.