UMI Z full review

UMI is undergoing a rebranding exercise, and this UMI Z is the last phone it will release before its name officially changes to UMIDIGI, short for UMI Digital. Somewhat confusingly an almost identical version of the UMI Z comes with a dual-camera at the rear and is known as the UMIDIGI Z Pro (reviewed here). The two phones should go on sale at around the same time, with this UMI Z currently up for preorder at GearBest and shipping from 25 February. Also see: Best Chinese phones

Right now you can pre-order the UMI Z in grey or champagne gold for just £192.40 (or $239.99). It works with all three UK 4G bands, and runs stock Android 6.0 Marshmallow with an OTA upgrade promised to Nougat in the coming months, so there are no usability issues here. As we'll see below it is a real bargain at this price, offering excellent value for money.

We would advise caution when buying from China, however, primarily because your consumer rights are not the same as in Europe, so should the product arrive faulty or not at all the process may not be as straightforward as you like. There's also the question of import duty, which is charged at 20 percent of the value on the shipping paperwork plus an admin fee of around £11. You can read more in our article on buying grey-market tech.

If you take the plunge you will be pleasantly surprised by the UMI Z. It's the world's first phone to run the deca-core Helio X27, which is MediaTek's latest flagship smartphone processor. Raw processing performance is up there with Qualcomm's Snapdragon 820, which is the chip 2016 flagship phones such as the LG G5 and HTC 10 make use of. (And you won't find one of those under £200.)

The UMI Z has an attractive aluminium-alloy unibody design, which houses two 13Mp Samsung cameras - one at the front and one at the back, with accompanying soft- and quad-LED flashes respectively. 

The battery is another highlight, made by Sony and rated at 3,780mAh. Some users might find they can squeeze two days of life from the UMI Z, and when it's time to recharge you can get a full day's juice in just 30 minutes. Also see: Best phones 2016


UMI Z review: Design and build

Let's start with the screen, since it forms a large part of the face of the UMI Z. This is a 5.5in panel, which makes the UMI Z a 'phablet'. It's reasonably weighty at 175g, as you might expect, but with slim dimensions of 154.6x76.8x8.2mm it doesn't feel overly large in the hand. This is in part helped by the fact it has smooth, rounded edges that glide into the 2.5D curved screen glass, but also the incredibly thin bezels to the left and right edges of the display.

The display resolution of 1920x1080 pixels is what's known as full-HD, and you certainly wouldn't expect anything higher at this price. It's pleasingly sharp, and with good screen brightness, contrast and viewing angles this Sharp IGZO display shouldn't give you any headaches. The UMI Z supports MiraVision, which allows you to adjust the display to suit your tastes.

UMI claims it had in mind the Bauhaus principle when designing the Z, which it says puts user experience above all else. It's crafted from a single block of space-grade aluminium-alloy, with two thin antenna strips integrated to the body top and bottom on the rear, and a stainless steel camera surround with sapphire glass lens protection.


It's certainly one of the best-looking UMI phones we've seen to date, and save for perhaps reducing the size of the CE logo on the back we find it difficult to pick holes in the Z's design. UMI has thought carefully about the positioning of everything from the power button, which falls neatly under the right thumb, to the selfie camera, which is slightly off-centre to match your stance when held in the right hand.

With its unibody build the UMI Z feels well put together, and with none of the usual creaking and flexing of plastic smartphones with removable rear panels it feels like a phone that will last. Of course, one of the down sides of the one-piece body is a non-removable battery, but UMI has cranked up the capacity to lessen this burden.

The rear camera does protrude slightly at the back, but to fit two 13Mp cameras and a large-capacity battery into a phone just 8.2mm thick is quite the achievement.


Two symmetrical rows of drilled holes sit either side of a forward-facing reversible USB-C port on the UMI Z's bottom. One houses a mic and the other a speaker, while you'll find the headphone jack up top. In its standard position at the top left edge is a pin-operated hybrid SIM tray, which allows you to insert either two Nano-SIM cards or a single SIM and a microSD card of up to 256GB capacity.

If we had to pick one thing we didn't love it would be the home button, which you tap or hold rather than press. It just doesn't feel natural to us. We're not especially keen on the removal of the navigation buttons at the bottom of the screen either, though these are accessible with a swipe up from the bottom of the screen. If you're happy not to use them you can tap the home button to go home, or long-press it to open the recents menu. 

UMI Z review: Core hardware and performance

The UMI Z has two key selling points that differentiate it from other similarly priced Chinese phones on the market. The first is the 13Mp selfie camera with soft LED flash, which we'll come on to later, and the second its Helio X27 processor. In time many phones will adopt this chip, but for now the UMI Z is your only choice should you want to use it.

The Helio X27 is a deca-core chip, which always sounds impressive on paper, particularly when you're comparing it to the likes of the Snapdragon 820 and 821, which are quad-core chips. Equally important, of course, is the technology each of those cores use and at which speed they run. This 20nm processor builds in two Cortex-A72 cores running at 2.6GHz for performance, and two groups of four Cortex-A53s tuned for efficiency. Also see: Best Android phones 2016


In raw processing performance we found the Helio X27 a close competitor to the Snapdragon 820, though with an inferior integrated GPU. To be fair to it, though, the Mali-T880 MP4 GPU inside the Helio X27 is said to show an 83 percent performance improvement over the Helio X20, MediaTek's first deca-core chip.

It's easy to think of the MediaTek Helio X-series chips as no-frills alternatives to Qualcomm's Snapdragon 820 series. They can't quite keep up in performance, but they offer more than most people will actually need and at a much cheaper price.

The UMI Z is fitted with 4GB of fast Samsung RAM, though it's still of the slower LPDDR3 variety than the LPDDR4 we see in many conventional flagships. It also has 32GB of storage as standard, and as we mentioned earlier you can boost this by up to 256GB simply by slotting in a microSD card.


We ran the UMI Z through our usual benchmarks and found some really very decent scores, particularly on processing performance. In AnTuTu 6, for example, it scored a very high 110,374 points, while Geekbench 4 clocked it at 1,796 points single-core and 4,265 multi-core.

This is right up there with flagship phones running the Snapdragon 820/821, including the likes of the OnePus 3T, Xiaomi Mi5s and even the Google Pixel.

It fell down in the graphics benchmarks, as expected, yet still turned in easily playable framerates in our tests. We recorded 27fps in GFXBench T-Rex, for example, as well as 18fps in Manhattan, 11fps in Manhattan 3.1 and 7fps in Car Chase.

In the Jetstream JavaScript benchmark the UMI Z turned in a respectable score of 56.02. You can compare its performance to some other flagship phones - many of which cost significantly more - in the chart below. Also see: What's the fastest phone 2017?

What all this means in the real world is that the UMI Z is entirely capable of playing any mobile game you like, watching any film you want, or doing whatever other task you fancy having a go at. You certainly don't need to worry about a lack of performance.

Battery performance is similarly good, with UMI quoting potential for 360 hours on standby, 60 hours of music playback or 14 hours of GPS navigation from the 3,780mAh Sony-made cell. In the real world, of course, no-one uses their phone for just one task, and usage can vary greatly day by day. We'd suggest that this is enough power to comfortably get all users through a full day, and lighter usage could result in two day's life.

The UMI Z doesn't support wireless charging, but there is fast charging when paired with a compatible charger. It can fully charge in 100 minutes, but if you have less time to spare UMI says you'll get enough power for a full day's use from just 30 minutes. Again, that really depends on your usage.

UMI Z review: Connectivity and extras

Very often we find with Chinese phones - especially those from Xiaomi and Meizu - that they do not support the 800MHz 4G LTE-FDD band that is used in the UK by all the major mobile operators. This is of particular issue to O2 customers - and those of companies which piggyback its network, such as Sky Mobile and Giffgaff - whereas other mobile networks do not rely on that single 4G frequency alone for LTE connectivity.

We're pleased to report, then, that the UMI Z works with all three 4G bands in use in the UK: 800MHz, 2100MHz and 2600MHz. This means you should get full network reception wherever you might have done on a previous phone or one sold specifically for UK use. Readers elsewhere should check the specifications to ensure the UMI Z will work correctly in their location - see how to tell whether a phone is supported by my network.


The UMI Z can support two Nano-SIM cards, meaning you can carry a single phone and yet separate business and personal lines, or perhaps insert a local SIM when you go abroad. It works in dual-standby fashion, meaning both SIMs can make and receive calls and texts at all times, but only one SIM can be specified for data usage. If you have no use for this feature then the second SIM slot also works as a microSD card slot. Also see our dual-SIM phones buying advice and group test

Aside from NFC, which would be necessary if you wanted to make mobile payments and then verify them using the UMI Z's integrated fingerprint scanner, virtually everything you need connectivity-wise is here. There's dual-band 802.11a/b/g/n Wi-Fi, plus Bluetooth 4.1, GPS and OTG.

UMI Z review: Cameras

The UMI Z is fitted with two 13Mp Samsung SK53L8 cameras - one at the front and one at the back. The UMIDIGI Z Pro comes with one at the front and two at the back. Also see: Best camera phone 


The selfie camera is one of the best you'll find, and as well as the very high resolution it has 1.4 micron pixels and a soft LED flash that can be turned on, off or to auto settings as required. Low-light is often a problem for self-portraits, so it's good to see UMI among those taking steps to fix it.

From the rear the UMI Z at first looks as though it has two 13Mp cameras; in fact, to the right of the primary camera is a laser autofocus. This is part of a dual-focus system, with the UMI Z also adding phase-detection autofocus. In common with the iPhone 7 it has a quad-LED flash, which it says is 50 percent brighter than most dual-LED versions for low-light shots. The UMI Z can shoot high-quality photographs, or video at up to 4K quality.

The camera app is straightforward, with real-time filters available with a swipe from the left-hand side, toggles for the flash and HDR mode along with a settings cog running across the top, and various modes at the bottom, including Videos, Face beauty, Photo, Pro Photo and Panorama. Below this you can access a shortcut to the Gallery app or switch to the selfie camera, and above there is a digital zoom function.

We were reasonably impressed with our test photos, but spotted a lot of noise when viewed at full size (click the images below to view them at full-size). They were also very easily blurred, with no image stabilisation seemingly in use. In Auto mode colours were vibrant and saturated, even in a gloomy London in January; HDR mode toned down this effect but left the images somewhat washed out.

See our test photos shot in Auto (1) and HDR (2) mode below.

UMI Z Auto


UMI Z review: Software

You won't find any bloatware, gestures or any other deviations from standard Android on this UMI Z: it is preinstalled with a stock version of Android 6.0 Marshmallow that includes a few Google apps but very little else. The notification bar and settings menus are exactly as you would expect to find them, and unlike Xiaomi and Meizu phones there is an app tray (as opposed to placing all app shortcuts on the home screen).The only real difference is the camera app, but it's easy enough to use.

We like this approach very much, since you don't get anything you don't want hogging storage space and slowing things down - it is Android as it was intended, which you get to customise as you so choose.

UMI has promised that Nougat will be released as an OTA upgrade in the coming months. It has advised that the software is ready to go, but it has chosen to wait until it can confirm it is as stable as the latest version of Marshmallow before upgrading users.


Read next: Best new phones


UMI Z: Specs

  • 5.5in full-HD (1920x1080) Sharp IGZO 2.5D display
  • Android 6.0 Marshmallow with Android 7.0 OTA upgrade available
  • 2.6GHz MediaTek Helio X27 deca-core processor
  • 875MHz Mali-T880 MP4 GPU
  • 32GB storage
  • microSD support up to 256GB or dual-SIM dual-standby
  • 4G LTE-FDD 800/1800/2100/2600MHz
  • dual-band 802.11a/b/g/n Wi-Fi
  • Bluetooth 4.1
  • GPS
  • OTG
  • fingerprint scanner
  • 13Mp Samsung SK53L8 PDAF camera with laser autofocus and quad-LED flash, 4K video recording
  • 13Mp Samsung S5K3L8 selfie camera with 1.4 micron pixels and soft LED flash
  • 3.5mm headphone jack
  • USB-C
  • 3780mAh battery with fast charging
  • 154.6x76.8x8.2mm
  • 175g