The ZenFone 4 feels like it has been a long time coming.

First announced in Asus’ native Taiwan back in June, then confirmed for India at the tail end of the summer, the 5.5in, dual-cam flagship promised a premium build and a photography focus, for not a lot of cash.

Now, finally, it has been officially confirmed for Europe, and I’ve been putting one through its paces.

With hardware that stacks up comfortably to the OnePlus, Honor and Motorolas of the world, and a price to match, is this the new sub-£500 phone to look out for? Here’s what I think so far.

Design & build

Wow, it’s been a busy year for the glass and metal sandwich school of smartphone design, hasn’t it? And now you can chalk up one more handset to add to the list.

The ZenFone 4 feels like a smooth pebble in the hand, with rounded corners and a slightly beveled frame. It’s a little on the chunky side, though, because it doesn’t curve at the sides like its more expensive rivals.

The flat glass back has a neat circular effect, a bit like a rippling water droplet, and the dual camera lenses sit completely flush to the body. The attention to detail is really very good.

An 18:9 aspect ratio and super skinny screen bezels would be asking too much at this price, but it still looks pretty slick from the front, too, with a fingerprint sensor positioned underneath the screen.

It’s a little troublesome, though - at least on the sample unit I tried. It would regularly misread my fingerprint, refusing to unlock the screen. It’s quick enough when it works, but it doesn’t always work. Which is irritating.


Not much to complain about here: Asus has squeezed a 5.5in, Full HD LCD screen, which puts the ZenFone 4 practically on par with the OnePlus 5.

It’s a sharp, colourful display with decent contrast, if not quite to the level you’d expect from OLED. Netflix streams still really pop, though, even in darker scenes.

Viewing angles are top notch, and it appears to get plenty bright enough to see clearly when you’re outdoors, although I’d want to do a lot more testing before I deliver a final verdict on image quality.

There’s a handy blue light filter, which should stop your late-night Facebook scrolling from keeping you awake, but there’s no option to schedule it automatically - you’ve got to toggle it on and off. Like a peasant.

No mention of HDR is hardly a surprise, seeing how this is more of a mid-range flagship, but it would have been a welcome inclusion that elevated the phone above its peers. Oh well.

One speaker at the bottom of the phone and a second in the handset speaker work together to deliver fairly loud audio, and was clear enough that I could enjoy a podcast in my hotel room without reaching for a pair of headphones.


Asus is talking a big game when it comes to the ZenFone’s dual rear cameras, even if, on paper, a 12MP+8MP setup doesn’t sound mind-blowing.

With Sony sensors inside and an f/1.8 aperture, though, along with some very useful optical image stabilisation, it stands every chance of taking fantastic photos.

Certainly in my test shots, which weren’t taken in the most favourable light, the level of detail on show was really quite impressive.

It’s not like Asus has followed the crowd with a telephoto lens, or gone for a monochrome sensor to ramp up the details either. The second sensor is wide-angle, letting you squeeze more into every shot. Only LG is doing something similar, so it’s great to see a wide-angle option at a more affordable price.

You get the usual selection of modes, including panorama, GIF animations and a completely manual Pro mode, which is fairly comprehensive: a histogram and three-axis virtual spirit level.

I’ll be putting the phone through some proper photography tests lat er this week, and won’t be delivering a final verdict until I’ve tried it in a variety of lighting scenarios, but at this early stage, things are looking pretty positive for this mid-ranger.


It might have gone beat-for-beat with the OnePlus 5 up to this point, but there’s one area where the ZenFone 4 does its own thing: the CPU.

Inside, it’s rocking a Snapdragon 630 CPU, a mid-range chip that replaces the much-used Snapdragon 625. Don’t think that this makes it a slouch, though: Android felt snappy enough while I was using it, with apps and games opening quickly.

Paired with 4GB of RAM, it should easily keep up with your day-to-day swipes and taps, and multitasking shouldn’t be a major problem either.

OK it’s not going to beat a Snapdragon 835 in any benchmark tests, and games might suffer a few dropped frames here and there, but from what I’ve seen, it’s a competent mid-ranger.

I’ll be taking a closer look at performance in a full review, to see if there are any problem areas you’ll need to watch out for.

On the plus side, a mid-range CPU should suck up less battery than a full-fat flagship chip. The 3300mAh cell inside the ZenFone 4 should be good for at least a day of use, with a bit left over in the morning if you forget to top up overnight.

There’s no wireless charging, but that reversible USB-C port should let you top up in just a few hours. Again, I’ll be testing battery life properly in the full review, coming soon.

Software & OS

Running Android Nougat out of the box, the ZenFone 4 is fairly typical for a 2017 flagship. Plenty of phone manufacturers have slimmed down the amount of bundled bloat they install on their phones, and Asus is no different.

The ZenFone 4 still has a fair few custom apps that replicate existing Google ones, but for the most part they don’t get in the way. The floating “selfie master” shortcuts that pop up in certain camera apps, though? Irritating to the max. Thankfully you can turn ‘em off with just a few taps.

It’s running Android 7.1.1 underneath a custom ZenUI interface, which is looking a lot less oppressive than previous versions. Beyond the custom app icons and redesigned notification drawer, it gets pretty close to stock.

I’m a big fan of the app drawer, which lets you organise and hide your apps in a custom order - much better than multiple home screens full of disorganised icons.

Asus ZenFone 4 initial verdict

There's certainly a lot to like about the ZenFone 4, and it's easily the most complete package Asus has ever released over on UK shores, but I wonder if it does enough to truly challenge the similarly-priced competition.

It is set to launch at £449, putting it directly up against the OnePlus 5 - which is running a near-stock version of Android, has an OLED instead of LCD screen, and has a significantly faster CPU. The Honor 9 has a similar glass design and equally drool-worthy specs, but costs £70 less. And if modular is more your thing, then the Moto Z2 Play can be picked up for the same amount. 

Battery life, picture quality and performance will be the deciding factors here - all things I'll need to spend more time with the phone to test before I can declare a winner.

Either way, it's great to see Asus finally giving us Brits a phone to look forward to. Expect a full review very soon.


Tech Specs 
5.5in 1920x1080 AMOLED
Qualcomm Snapdragon 630 octa-core
Dual 12MP+8MP, f/1.8+f/2.2 rear with PDAF, OIS, dual-LED flash. 8MP front
64GB on-board, microSD expansion
3300mAh non-removable
Android 7.1.1 Nougat w/ ZenUI
155x75x7.7mm, 165g