Asus Zenfone 9 reviewed

By Calvin Jones. The Asus Zenfone 9 packs a lot into a small package. With Qualcomm’s latest Snapdragon 8+ Gen 1 flagship chipset at its core, the handset delivers class-leading performance, combined with excellent battery life, a stunning 5.9” FHD+ 120Hz AMOLED display, up to 256GB of storage and a whopping 16GB of RAM, and a gimbal stabilised 50MP main camera for steady photos and ultra smooth video.

Could this be the best compact Android smartphone on the market in late 2022?

Asus Zenfone 9: a pocket-sized phone that’s big on performance


Superb performance

Compact, pocket-friendly design that’s easy to use one-handed

Great build quality, a premium feel and full IP68 water and dust rating

There’s a headphone jack… on a flagship handset… in 2022. A headphone jack!


Commitment to software support is well off the pace for a phone of this calibre. Asus specifies only 2 guaranteed Android updates and a further 2 years of security updates. That falls a long way short of the competition.

Absence of wireless charging is a surprise for a flagship-level handset in 2022

Charging speed from the bundled 30 watt charger is OK, but hardly cutting edge

Asus Zenfone 9: Full Review

Over recent years, smartphones have become progressively larger, to the point where today’s flagship and mid-market handsets feature displays pushing 7 inches. They may sport sleek, modern designs, but there’s no getting around the fact that any phone that big is going to feel unwieldy in an average-sized hand, and cumbersome when slipped into a pocket or purse.

Many people relish the extra screen real-estate offered on larger phones, and are prepared to put up with the inconvenience, but there’s a sizable cohort of the market (myself included) that craves a smaller, more manageable device. We want a phone that sits comfortably in the hand, and that’s easy to use one-handed without becoming a contortionist.

The trouble is, if you’re looking for top tier performance and specs in a smaller form factor phone in 2022, your choices are seriously limited.

Small phone, minimal compromise

Choosing a compact phone usually means taking a serious hit in areas like performance, build quality, feature-set, battery life and more. However, one thing that sets the Asus Zenfone 9 apart from most of its competition is that you really don’t have to compromise very much. Remarkably, you get true flagship-grade specs and performance that rivals anything currently available, just in a smaller, more manageable and much more pocketable package.

Squeezing so much into a smaller device means Asus inevitably had to leave some things out. On that score though, they’ve made what I think are sensible choices, and for most people, in most day-to-day use cases, those omissions (we’ll touch on exactly what they are later) are unlikely to prove deal-breakers.

The result is a remarkably accomplished and uniquely capable compact flagship handset.

Asus Zenfone 9: First impressions

The Asus Zenfone 9 comes in a stylishly understated grey box with a large 9 printed on the top along with minimal embossed Zenfone branding. Inside you’ll find the Zenfone 9 itself, a USB C to USB C charging cable, a 30 watt USB C charging adapter (a welcome addition that’s becoming scarce with new phones), a sim-ejection tool and a snap-on protective hard case to shield your new phone from bumps and scrapes.

The phone itself is noticeably diminutive. Sitting alongside a regular 6.7” handset it looks positively dainty, and in the hand it just fits. It’s the most natural feeling phone I’ve handled in quite a while. At just 169g it’s light too, yet still has a solid, premium feel.

As soon as I held this phone in my hand, I knew I was going to love it.

Asus Zenfone 9: Appearance and design

The Zenfone 9 uses a flat front panel, eschewing curved edges and giving the phone a sharp, contemporary feel. A flat panel all the way to the edge also gives Asus a smidgen more volume to work with under the hood — which is a smart design choice when you’re trying to shoehorn so much tech into a small footprint. There’s a punchhole for the front facing 12MP selfie camera in the top left of the display and an earpiece/speaker grille incorporated into the top bezel.

Around the sides of the phone there’s a solid aluminium strip that helps give the phone its premium feel. It’s brushed silver on the Moonlight White model, and matte black on my Midnight Black review unit and other colour variants (Sunset Red and Starry Blue).

On the right hand side you’ll find the volume rocker and a multi-function power button that doubles as a super-fast and accurate fingerprint scanner AND a programmable feature button (double press and/or long-press to take a specific action or launch an app) AND a swipe-able gesture surface that lets you swipe down/up on the button to show/hide your notification bar, scroll web pages and more. While that’s a cool feature, I kept accidentally swiping down the notification bar while doing other things, so I soon turned it off.

On the bottom of the phone you’ll find a second speaker grill, USB C port, a microphone pin-hole and a sim tray sporting dual nano-sim support, but no SD Card expansion option. On the top edge you’ll find another microphone pin-hole and, wonder of wonders, an actual physical 3.5” headphone jack. Thank you Asus! While I do use bluetooth earbuds, it’s always great to have the option to just physically plug in if you need to.

Around back, Asus has ditched the glass and gone for a unique polymer material (a plastic composite in other words) that has a texture unlike anything I’ve felt on a phone before. It feels almost like very fine emery paper and feels anything but cheap. It’s grippy and tactile, and I found myself constantly wanting to stroke it. Just as well it seems impervious to fingerprints, unlike the numerous glass-backed phones I’ve used before. It should also be much more robust than glass, absorb impact better and won’t shatter.

There is some subtle Zenfone branding on the back that’s not too obtrusive, but the stand out design element is the huge dual camera modules housing the 50MP main shooter and 12MP ultrawide. But more about those later….

I really like the design of the Zenfone 9 — it’s different enough to be interesting in a world where smartphones have become largely ubiquitous, yet retains a familiarity that makes moving to it seamless. My only criticism on the design front for a phone pitching itself as a 2022 flagship is the uneven bezels. The top (forehead?) is ever so slightly wider than the sides, and the “chin” is wider again. It doesn’t really affect the phone in use — but other phones at the same price point have uniformly narrow bezels giving an almost edge-to-edge display that just feels more premium.

Asus Zenfone 9 Performance

Raw power

When it comes to performance the Asus Zenfone 9 doesn’t pull any punches. Under the hood it’s powered by Qualcomm’s latest and greatest Snapdragon 8+ Gen1 platform that’s used in ultra-high-end flagships and the best dedicated gaming phones (like Asus’s own ROG Phone 6 Pro). Paired with a combination of RAM and storage ranging from 8GB/128GB up to the 16GB/256GB unit I tested, this diminutive smartphone is an absolute beast in terms of raw performance, and can more than hold its own with pretty much any phone out there.

It flies through day-to-day tasks with no hint of lag or stutter, apps open practically instantly, and multi-tasking even the most demanding apps is a breeze: it just never gets bogged down.

As you might expect, given those specs, the Zenfone 9 can easily do double duty for some impromptu gaming, taking even the most demanding Android games, like Genshin Impact, in its stride even with graphics and performance settings cranked to the max. One caveat here though: while it has more than enough power to run any game you choose, the Zenfone 9 lacks the physical space to accommodate the fancy cooling shenanigans you’ll find in a dedicated gaming phone. While the Snapdragon 8+ Gen 1 is more efficient and runs cooler than its predecessor, under heavy sustained load the Zenfone 9 does warm up noticeably and during prolonged gaming sessions and/or benchmarking tests, for example, you will notice thermal throttling as the phone tries to offload excess heat.


The display on the Zenfone 9 is a vibrant 5.9” AMOLED panel with Full HD+ resolution and a refresh rate of 120Hz (with dynamic switching between 60, 90 and 120Hz available to optimise viewing depending on the app or content you’re viewing) for that buttery smooth flagship experience. It is not an LTPO panel, however, so while it switches between those fixed refresh rates, and can’t provide anything in between, or drop to the lower power-saving refresh rates as offered by flagship devices with LTPO.

Colours are punchy out of the box with a colour accuracy Delta-E rating of <1 and several modes and customisation options so you can play and tweak to your hearts content. There’s full support for HDR 10 and HDR 10+ too for your mobile viewing pleasure, and the display is plenty bright enough — with a specified peak brightness of 1100 nits, making it relatively easy to see in bright sunlight.

That pretty panel is well shielded too, by a sheet of the latest Corning Gorilla Glass® Victus, making it pretty durable (if you want to keep that display pristine, it’s worth noting there’s no factory fitted screen protector included, there are however plenty of third-party options available for the Zenfone 9). It’s also fully IP68 certified, so no need to worry about splashes, using it at the beach or even the occasional accidental submersion.

Battery and Charging

One area where you expect to make compromises with a compact phone is battery life. There’s less space, after all, to fit in a larger battery. It’s an issue that was noticeable in the Zenfone 9’s predecessor, the Zenfone 8, and that plagues some other compact alternatives, but thankfully battery life on the Zenfone 9 isn’t really an issue. The 4300mah cell they’ve squeezed into the unit, coupled with the efficiency gains of the Snapdragon 8+ Gen 1, easily powers the Zenfone 9 through a full day of moderate to heavy use on a single charge with juice to spare.

I took the review unit with me on a birding trip to Shetland as my main phone. I used it extensively most days from 7am to around midnight, and it was always somewhere between 20% and 40% when I plugged it in to charge at night. Under normal to moderately heavy usage you’ll never have to worry about running out of power. At a push the Zenfone 9 will happily get you part of the way through the next day too if you forget to plug it in.

When you do need power, the bundled 30 watt power brick will take you from 0-25% in just over 10 minutes, to 50% in a shade over half an hour, and takes a little under an hour and a half to reach 100%. That’s fairly standard fare these days, and not great for a 2022 flagship. With 120 watt and even 180 watt charging becoming commonplace, 30 watt charging feels a bit pedestrian.

Having said that, if your phone easily makes it through a full day on a single charge, and you just plug it in overnight, like most people, it’s a moot point, and charging at 30 watts is likely to be kinder to your battery in the long run.

There is no wireless charging option here — which is one of the omissions that Asus says they made to fit everything else in. Other phones of this size do have it — but they make compromises in other areas where the Zenfone shines, so it’s one of those swings and roundabouts situations.


The back of the Asus Zenfone 9 is dominated by the imposing dual camera array. The first of these is the 50MP main shooter, the second a 12MP Ultrawide. Mercifully that’s it: it’s refreshing not to have questionably useful depth-sensors or marginal-quality macro options cluttering up the phone’s rear, just for the sake of an elevated camera count. There’s also no telephoto option, which is a shame, but another of those space-related compromises that are inevitable in a phone this size. Around the front you’ll find an unobtrusive 12MP selfie camera tucked away in the top left corner of the display.

The large circular camera bumps promise a lot, and raise expectations in terms of camera performance, and by and large the Zenfone 9s cameras do a decent job in most situations. However, that main sensor is the excellent but now ageing Sony IMX 766, which is no longer considered a top-flight flagship sensor. Camera performance is good, but not outstanding, and certainly won’t be ousting the iPhone 14 Pro Max or Google’s brand new Pixel 7 Pro at the top of the smartphone camera league.

The Zenphone 9 has a trick up its sleeve though. The main camera combines the sensor’s built-in optical image stabilisation with a hybrid six-access gimbal mount that moves the whole lens and sensor assembly to compensate for camera movement. It works very well, and results in impressively sharp handheld shots indoors in marginal light, and ultra-smooth handheld video that looks as if it was shot with the phone mounted on a physical gimbal.

All three cameras can shoot video at up to 4K60, and that main shooter can jump to 8K24 should the mood take you. There’s also slo-mo capture at up to 480fps in 720p, 240fps in 1080p and 120fps in 4K.

All three cameras feature autofocus. That includes the selfie camera, which is unusual even on flagships. It gives more consistent results than the usual fixed-focus affairs, and delivers results that are very good as a whole in decent light. Autofocus on the ultrawide camera means that it can double up as a reasonably capable macro camera for close up shots, with results that are often more useful than those of gimmicky dedicated macro cameras. For landscapes the ultrawide gives you a wider perspective, albeit at the expense of some of the detail and enhanced dynamic range offered by the main camera.

Photos from the main camera are, by and large, excellent across a wide range of conditions and scenarios and there are plenty of options in the native camera app to tailor it to your liking. The biggest issue I had with the cameras was software related. Asus’s algorithm can be a little overzealous in its automated post processing at times, resulting in images that can look over-sharpened and unnatural. It doesn’t seem to affect every image, or happen consistently, but it does seem to impact images from all three cameras. Hopefully that’s something Asus can address in a future software update, but it does serve as a reminder of how far ahead the likes of Apple, Samsung and Google are with their post-capture AI smarts.

You can hop into pro mode on the native camera app (which offers plenty of control over how you capture your images), or try a third party camera app like Open Camera for a consistently more natural looking image.

You can see a selection of images shot on the Zenfone 9 here.


I’m no audiophile, but the Dirac tuned linear speakers on the Zenfone 9 sound very good to my ears. There’s lots of bass and while they don’t get really loud, they’re loud enough for a small phone, the sound is rich, and doesn’t distort as you push up the volume.

I’ve seen reviews rating the speakers from outstanding to mediocre, which I guess says a lot about how subjective sound is. Overall, for smartphone speakers on a compact phone I’d say Asus has done an admirable job here.

Add in Snapdragon Sound, Qualcomm’s aptX Adaptive tech, multiple customisable audio profiles, a dedicated audio wizard and yes, even a 3.5mm headphone jack, and the Zenphone 9 has your audio needs pretty much covered.


The Zenfone 9 offers full 5G, 4G, 3G and 2G connectivity to all Irish mobile networks and most international networks. One thing to note is that it doesn’t support 5G mmWave bands, so it won’t connect to 5G on some US networks.

Apart from its mobile connectivity, the phone supports the latest WiFi 6/6e standard with tri-band 2.4, 5 and 6 GHz support. It has Bluetooth 5.2 with support for LDAC, AAC, Qualcomm® aptX, aptX HD, aptX Adaptive and aptX Lossless, and of course it supports NFC for contactless payments and other NFC functionality.

When it comes to location and navigation the Zenfone 9 support GPS (L1/L5), Glonass (L1), Galileo (E1/E5a), BeiDou(B1i/B1c/B2a), QZSS (L1/L5) and NavIC, so you’re unlikely to lose your way using this phone.

Asus Zenfone 9 Software

The Asus Zenfone 9 ships with Android 12, overlaid with the very light-handed Zen UI. It’s pretty much as near as you can get to a Stock Android experience on a non Pixel phone. There’s no real bloatware added — just a few pre-installed apps like Netflix and Facebook that most people will install anyway, and that are easily removed if you don’t want them.

If you’ve used stock Android, the menus and settings will all feel reassuringly familiar, and the little additions and augmentations Asus has made are genuinely useful for the most part.

On the software front the Zenfone 9 is an absolute joy to use, and a refreshing change from the bloated, over-engineered and obtrusive skins some manufacturers shoehorn on top of Android.

The one downfall on the software front, and it’s a big one, is Asus’s limited update support window. I hope this changes, as it’s something pretty much every reviewer of the phone laments, but for now at least, Asus is committing to just two major Android updates and at least two years of security updates for the Zenfone 9. That falls far short of what other brands are offering for their flagship models, and frankly it’s not good enough for a phone of this calibre.


I’ve really enjoyed using the Asus Zenfone 9 as my main phone over the review period. I’d go as far as to say this is my new favourite phone. I love the smaller form factor, the easy one-handed use, the way it slips effortlessly into my pocket, never worrying about the battery running out, and the way it takes everything I can throw at it in its stride.

It’s not perfect, but it is a really compelling combination of design, features, performance and ease of use that just work together beautifully. Asus got a lot right with this phone, so if you’re in the market for a high-end smartphone, but fancy something a bit more compact, take a closer look at the Zenphone 9. It doesn’t disappoint.

About the Author

Calvin Jones is an author and online content specialist based in West Cork Ireland. Alongside his writing projects, he runs Ireland’s Wildlife, helps small business clients improve their websites and reviews the latest tech gadgets.

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