Xiaomi Mi 8 full review
Xiaomi announced the Mi 8 in May 2018, alongside the Mi 8 SE and Explorer. At first available only in China, when Xiaomi officially launched in the UK in November it also announced the cheaper Mi 8 Lite (reviewed) and Mi 8 Pro (reviewed).
The Mi 8 has in February 2019 been superceded by the Mi 9, which now retails at £499, and in February 2020 we have seen the Mi 10 announced in China. The Mi 8 still retails at £459 in the UK, but you'll find it online for significantly less - Amazon and Laptops Outlet both list it below £250.
Mi 8 remains an incredible-value smartphone, especially where you can find it on offer, but we can't overlook the enhancements made in Mi 9. Not only does it add the in-display fingerprint sensor we saw in the Pro and Explorer editions of Mi 8 as standard, but it enlarges the screen, reduces the notch and increases the screen-to-body ratio. There's a new Snapdragon 855 processor that makes it faster than even Galaxy S10, as well as the addition of a triple-lens camera (with 48Mp lens headlining) at the rear and 20W wireless charging.
As such, Mi 9 addresses many of our gripes with Mi 8. If it's even fair to call them gripes.
In common with many Chinese phones the standard Mi 8 has an amazing specification at a crazy-low price, but it lacks some of the features we were so looking forward to in the lead up to its announcement. Thus the standard model has no in-display fingerprint scanner, which would have given it a lead over better known rivals such as Samsung, Apple and LG, there's no waterproofing and, despite its inclusion in the Mi Mix 2S, there's no support for wireless charging - in any of the three editions.
Something that has potential to divide fans is a completely new feature to Xiaomi's phone line: the dreaded screen notch. As seen in the likes of the iPhone X and LG G7, it allows the screen to cover more area on the front of the device, while retaining an area in which to keep the selfie camera, sensors and earpiece speaker. Thus the Mi 8 has a screen-to-body ratio bordering on 87%, and now a larger display than ever at 6.21in.
No complaints there, but the notch is not universally admired for its aesthetic appeal. In our minds it's certainly better than the alternative solution provided by the Mix, placing the selfie camera below the screen and requiring the user to turn upside down the phone to make proper use of it. And it gives the Mi flagship line a whole new look that is befitting of such premium devices.
Also see: Best Xiaomi Phones
Where can you buy the Xiaomi Mi 8?
Xiaomi's Mi 8 is officially available in the UK from £399, available on contract through Three and sold everywhere from Amazon to Argos, Currys, John Lewis, Carphone Warehouse and even the Mi UK store. There's also a Mi outlet in London's Westfield shopping centre where you can try before you buy.
This is a phone with features and performance in line with the likes of the Galaxy S9, LG G7 and OnePlus 6, and it costs a fraction of the price.
If you like the sound of the Mi 8 at an even cheaper price, also check out the Xiaomi Pocophone F1.
Xiaomi Mi 8 Design & Build
At first glance the Mi 8 is immediately set apart from all Mi flagships before it by the most significant new upgrade to this phone: the screen. It brings the new Xiaomi flagship kicking and screaming into the future, which is exactly where it deserves to be.
Okay, so it's still not got a higher than full-HD resolution, and we're beginning to wonder if we'll ever see Quad-HD or Ultra-HD on a Xiaomi phone, but the Mi 8 has a gorgeous AMOLED panel that is rich in contrast (up to 60000:1, so the company claims), with punchy colours and excellent brightness. We measured 408cd/m2 with the Spyder, making this an ideal device for use in direct sunlight - something we have actually been able to test in the UK for once!
Moreover the Mi 8's display is larger than on any Mi flagship before it, up from 5.15in to 6.21in. The fact this has added only a centimetre to the phone's height, which is also 4mm wider, is quite a remarkable feat. Love it or hate it, for this we have to thank the new screen 'notch' (which can be hidden in the screen settings if you really dislike it) - and the fact you'll now find the fingerprint sensor on the rear.
Actually, the latter is a significant design change for us personally: we hated the pressure-sensitive button that didn't quite feel like a proper button on the Mi 6. With this moved to the rear the Mi 8's top bezel and chin are now much shorter, and with minimal space either side of the display it has a screen-to-body ratio of 86.7%.
The display is taller without being proportionately wider, adopting the new 18.7:9 aspect ratio that we're seeing from flagship phone makers all over the world. With more screen space available to apps they offer a much more enjoyable multimedia- and browsing experience, and they just look so much better.
By default the Mi 8 has recent apps, home and back software buttons at the bottom of the screen, but it's possible to switch these off and opt to use full-screen gestures instead. To access the home screen you quickly swipe up from the bottom and let go, while the same gesture with a pause before lifting your finger will open the Recents menu. To go back you swipe in from the left- or right edge of the screen.
So from the front it's all change for the Mi 8, but you'll also notice some differences at the rear. Where the dual-camera previously lay flush to the body in the top left corner it now juts out in a vertical alignment toward the top left side. We have to say we don't love it, though it doesn't stick out far enough to cause any stability issues when lying flat on a desk. If anything it seems to give the slippery glass body a little more grip, which can't be a bad thing if you hope to keep it intact.
This glass is gently curved on all four sides, but more so to the left and right, making the larger than ever Mi flagship feel less cumbersome in a single hand. The glass front and back is separated at the middle by a 7000-series aluminium frame, which is about as premium as it gets in 2018 smartphones.
So with all this glass it's a real shame there's no support for wireless charging, because this is one area in which Xiaomi lags behind its competitors and in which consumers are really starting to sit up and take notice how convenient it is. The Mi 8 also lacks any form of waterproofing, which was tipped to be added to the line this year.
At 175g the Xiaomi feels reassuringly weighty in the hand, without being too heavy, and it's 7.6mm thick body aids the impression of a super-slick premium design.
Xiaomi Mi 8 Hardware & Performance
In line with all 2018 flagships the Mi 8 has seen its core spec boosted to the Qualcomm Snapdragon 845 (here clocked at 2.8GHz) and 6GB of RAM. The standard model that we review here also has 64GB of storage, but the Mi 8 also comes in 128GB and 256GB variants. The latter is important because there is no support for microSD.
It's a breathtaking combo that offers performance in line with flagship phones costing several hundred pounds more. It particularly shone in graphics tests, though this is almost certainly down to its lower-resolution screen. In use you absolutely cannot fault the Mi 8's performance: speed is not something you'll ever need take into consideration.
Even battery life is good, with a 50mAh bump over the Mi 6 (now up to 3,400mAh) we recorded 7 hours 10 minutes in the Geekbench 4 battery test, which is higher than its competitors and evidence that will keep going as long as you do.
And while we're sad about the lack of support for wireless charging, support for Quick Charge 4.0 is music to our ears. Convenience is neither here nor there when you can recharge a phone as quickly as you can the Mi 8.
We've compared our benchmark results to some other flagships in the chart below. As you can see, there is no compromising on performance to keep down costs.
Xiaomi Mi 8 Connectivity & Extras
Xiaomi bills the Mi 8 as the first Snapdragon 845 phone to support dual-frequency GPS, which means in navigation it should prove more accurate than any other phone.
It's nice to see support for all three 4G bands used in the UK, since support for the 800MHz band is often left out in Xiaomi phones, and there's also dual-sim dual-standby functionality if you wish to use two SIMs. This might be useful if you want to separate work and play, for example, or if you're travelling abroad and would like to use a local SIM to keep down costs.
There's also dual-band 802.11ac Wi-Fi, Bluetooth 5.0, NFC and the aforementioned fingerprint sensor, which works flawlessly.
One more new feature in the Mi 8 is a 3D-sensing camera at the front, which is basically the same thing as the iPhone's Face ID. It's less secure than a password or PIN, since it could be unlocked with a photograph of you or by others with a similar appearance, but it's pretty cool nonetheless and almost certainly a factor in Xiaomi's reasoning in moving the fingerprint sensor to the rear.
In our tests it just worked all by itself in the background, and you forget it's even running until someone else tries to unlock the phone. It also works in the dark.
As in the Mi 6 there's no headphone jack, so you're reliant on USB-C for audio. An adaptor is supplied in the box, along with a silicone case - a nice touch, given that it can often take a few weeks for delivery of Chinese phone cases.
Xiaomi Mi 8 Cameras & Photography
As before the Mi 8 features a dual-camera at the rear with two 12Mp lenses. One of the lenses is a Sony IMX363 with four-axis OIS, dual-PD focus, f/1.8 aperture, 1.4um pixels and a dual-LED flash; the other a 12Mp Samsung S5K3M3 lens with 1.0um pixels and an f/2.4 aperture, which enables telephoto and portrait capabilities. As well as 12Mp stills it can shoot 4K video, but OIS is supported on only one lens.
It's actually the same camera module as on the Mi Mix 2S, though it is running newer and improved firmware. Xiaomi says the Mi Mix will be upgraded accordingly.
It uses artificial intelligence to boost the photography skills of the primary camera, and as we saw on the Mi Mix 2S the camera is able to automatically select one of 206 preset scenes to help you get the best shot. It isn't always clear what it's doing, but that doesn't perhaps matter if you're the type of person who would rather pick up and shoot than fiddle around with manual modes.
It's all change at the front, with a 20Mp selfie camera replacing the previous 8Mp lens. Xiaomi is seriously talking up its selfie-shooting skills, with a 'Micro-Plastic' Beauty mode that also uses AI for deep learning of facial features. It supports fine adjustments, image background blur, and real-time previews.
In our test shots we found the Mi 8 camera to be very good. (You can see a few of our shots below, in auto and HDR modes, plus a low-light shot.)
Colours are bang-on, with sharp lines and great detail. At 100% a very small amount of grain is visible at the far edges of shot, but the level of detail is otherwise incredible, with the Mi 8 able to pick up individual bricks and road names at street level on the other side of a busy dual-carriageway from our seventh-floor roof terrace.
Low-light photography is generally very good, with plenty of detail on text and the camera able to pick out different shades of black. Viewed at 100%, again, some noise is visible, but the overall image quality is strong.
Xiaomi Mi 8 Software
Although MIUI 10 was announced during the same launch event as the Xiaomi Mi 8, the Mi 8 runs MIUI 9.5. It's based on Android Oreo and has all the same features, and then some.
We've touched on a few already, but there's also a Dual Apps mode that lets you run two instances of each app (handy if you're using two SIMs or allowing someone else to use your phone), a one-handed mode that can make the device more friendly to smaller hands, and a Quick Ball option that places onscreen quick access to frequently used functions.
New to the Mi 8 and also seen in the Mix 2S is the Guide, which is a swipe in from the left of the main home screen. It lets you quickly jot down notes, add shortcuts to frequent apps, and alerts you to upcoming calendar events.
Xiao AI is preinstalled, which is Xiaomi's voice assistant, but if you don't speak Mandarin it's currently of no use to you. We didn't test this feature and recommend you instead install the Google Assistant if voice control is your thing.
MIUI is quite the departure from plain old Android, with a redesigned Settings menu (thankfully with Search function), removal of the app tray and Xiaomi's own apps for everything you'd normally use Google services. Google Play was not preinstalled on our review sample, but it is easy to install. You can then add whichever Google - or other - apps you like as required.
Xiaomi Mi 8: Verdict
At significantly less cost the Mi 8 is a tough rival to more familiar flagship phones on the UK high street, though it has now been updated with Mi 9. It misses a few features such as waterproofing and wireless charging, but there's a gorgeous 18.7:9 AMOLED display, 3D face recognition and some seriously powerful hardware. A beautiful design and high-quality build round off a fantastic deal. We strongly recommend purchasing the Global edition, but it is possible to install Google services even on the Chinese edition via the Mi App Store.
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Xiaomi Mi 8: Specs
- MIUI 9
- 6.21in Full-HD+ (2248x1080) 18.7:9 AMOLED display
- 2.8GHz Qualcomm Snapdragon 845 octa-core processor
- 6GB RAM
- 64GB storage
- 4G FDD-LTE B1/2/3/4/5/7/8/12/17/20
- dual-SIM dual-standby (2x nano)
- dual-band 802.11ac Wi-Fi
- Bluetooth 5.0
- rear fingerprint sensor
- dual-frequency GPS
- dual-camera: Sony IMX363 12Mp + 12Mp, four-axis OIS, dual-PD focus, 1.4um pixels, dual-LED flash, 4K video
- 20Mp selfie camera, 1.8um 4-in-1 pixels
- 3400mAh battery, Quick Charge 4.0