While Huawei has dabbled with OLED, it chose an IPS LCD for the Mate 9. The LG V20 also uses an IPS screen but both are at very different resolutions - QHD/513ppi for the V20, 1080p/373ppi for the Mate 9. We think 1080p is a bit of a stretch at 5.9", but it works out well enough (if it was an OLED, the PenTile matrix would have been an issue).
The Mate 9 screen offers superb contrast, topped by very few devices - 1,600:1, compared to LG V20's 1,100:1. The maximum brightness of both is pretty close, but the Huawei has deeper blacks. Images really pop on this display.
|Display test||100% brightness|
|Black, cd/m2||White, cd/m2|
Both displays are hurt by the reflectivity of the glass above them - the LG V20 more than the Mate 9. So even though the sunlight numbers appear fairly close, in practice we had an easier time reading the Huawei display. Also, it gives you full control over the entire range of brightness while with the LG you get the peak brightness levels only when the Auto brightness mode decides to go into overdrive.
While contrast can make an image pop, most makers also boost the color saturation. Neither LG nor Huawei managed to calibrate their displays perfectly and they achieved average deltaE of around 5 and a maximum of around 9. The Mate 9 has a Warm mode, which drops the average a bit but despite what the mode is called, the screen maintains its blue tint.
The color accuracy is "good enough" but not terribly exciting for a flagship. Apple is pushing Wide Color Gamut displays, Samsung tried to bring HDR to mobile (with the Note7, perhaps it will have another go with the S8).
We mentioned LG V20's second screen in passing, but didn't go into details. Time to change that - the 2.1" line display has the same pixel density as the main screen but is always on. This offers at-a-glance info and instant shortcuts (no need to unlock the phone).
This display offers vital functionality when the main screen is on too - we especially like it for multitasking, it's a desktop-like feeling to tap on an app's icon and jump back to it.
Winner: Tie, again. The Huawei Mate 9 flirted with victory, its larger display offers impressive contrast ratio and better legibility in broad daylight. Still, only 1080p resolution on a 5.9” diagonal? We don’t mind it much, but at this price range we expect the best.
The LG V20 display is indeed sharper and the secondary screen is marketed as a perk. We think an Always On Display is better of at-a-glance information and the added UI features that live on the extra screen are mostly limited to LG software.
Both phones feature modems with blazing fast 4G LTE - up to Cat. 12 with 3 Carrier Aggregation. The LG has an extra band, AWS-3, which will enable better LTE reception in metropolitan areas in a few years' time (carriers need time to upgrade their networks). Both phones offer VoLTE for higher quality audio in calls.
They also offer fast Wi-Fi a/b/g/n/ac and Bluetooth 4.2, but only the LG has aptX. This continues the story of high-quality sound. If you use wired headphones instead, the quad-DAC (ESS ES9218) produces less noise. The LG V20 can also use USB-C headphones if you have them (you probably don't but still).
Both phones have USB-C ports, but the Huawei Mate 9 is wired only for USB 2.0 speeds. The LG V20 supports the much faster 3.0 standard, but LG didn't include the right cable for it so you'll be getting USB 2.0 speeds unless you bring your own cable.
If the head unit in your car supports MirrorLink, you can enjoy Android Auto with either phone. And they have IR blasters to control stuff at home too. That leaves one extra advantage for the LG - FM radio. Many have stopped using it, but some still turn it on daily.
Winner: LG V20. The advantages may not be immediately visible, but you may appreciate them in time. The benefits of aptX-compatible Bluetooth headphones will only work with the V20. AT&T and co. will roll out the AWS-3 sooner rather than later and you'll get better coverage. You may even get a USB-C 3.0 if you still transfer data over wires. And hey, it's better to have FM radio than not have it.
The Huawei Mate 9 comes with the bigger battery (4,000mAh) and faster charger (22.5W). Perhaps the LG V20 will be more efficient with its hardware (3,200mAh battery, 16W charger).
That turned out not to be the case, the V20 lasted a good deal less in web browsing and video playback. The endurance rating is lower too, but we tested the worst case scenario - when the second screen never turns off. Even without that, the lower times in the two tests means the battery will deplete faster. You could, if you wanted to, carry a spare battery, though we think few will do that.
We tested Huawei's SuperCharge tech and watched the battery percentage climb quickly - from 2% to 20% in 10 minutes, to 40% in another 10 and on to 50% in another 5 minutes. You can get to 90% in an hour total, but things slow down significantly from there.
Still, that's 90% of a 4,000mAh battery. The LG V20 takes about an hour and a half to fill its battery from flat to full.
Winner: Huawei Mate 9. Faster to charge, slower to deplete is what we want to hear. You can browse the web nearly twice as long on the Mate 9 as you can with the V20, a huge difference!