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.
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.
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 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
- 4GB LPDDR3 RAM
- 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
- 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
- 3780mAh battery with fast charging