Asus ROG Phone II review

120Hz AMOLED screen

"The world's first and fastest 120Hz 1ms AMOLED with 240Hz touch response" - that's the official title Asus PR is sticking with and it does sound mighty impressive to the right display enthusiast crowd. A marriage between OLED, with its infinite contrast, perfect blacks, punchy colors and fast pixel response times and high-refresh rate technology is a coveted one and has been a long time coming.

Without getting too technical, for all their benefits OLED pixels do have a few inherent disadvantages. Most notably, due, in part to their organic nature, they tend to be quite slow when completely turning off and turning back on. In technical terms this is referred to as MPRT (Moving Picture Response Time) and is quite different from the otherwise stellar GtG (Grey-To-Grey) OLEDs have. The latter can easily go as low as the advertised 1ms on the ROG Phone II, since such a color change does not require the OLED pixel to be turned off.

In a theoretical perfect 60Hz OLED display, you can expect a minimum persistence in pixel visibility time of about 16.7ms. That is the primary cause of the so called "smearing" or "jello" effect on most smartphone OLED panels. There are certain approaches to combating this OLED blurriness, like rolling scan (commonly used in VR headsets) and Black frame insertion (BFI). The best thing you can do to reduce the effect, however, is a higher refresh rate. Generally speaking, this is what makes the 120Hz native refresh rate of the ROG Phone II so valuable for a crispy fast moving image - great for gaming and general UI operation.

Once you experience the smoothness and sharpness of moving images on the ROG Phone II at 120Hz you won't want to go back. It pretty much blows any other smartphone display out of the water.

Of course, this is a bit of an oversimplification of the tech and hurdles of high refresh rate and OLED panels in general. If you want a more in-depth dive on the matter in a future article, be sure to drop a comment.

Unfortunately, Asus doesn't really disclose all the inner-workings of its industry-leading 120Hz panel. The main thing we would be interested in from a consumer standpoint is whether or not some compromises like constantly running all the pixels in dark grey to reduce response times and blur have been put into place. This is somewhat of a common practice. The major downside being potentially not ideal blacks and more importantly - much higher power consumption on average. OLEDs are great for power efficiency, but not if you keep all the pixel on all the time. Unfortunately, we did record some unfortunate spikes in power consumption using the 120Hz mode on the ROG Phone II, which you can read about in the battery section.

As for the black concern, we can at least say with confidence that our color accuracy test picked up perfect blacks. Asus talks a pretty big talk regarding colors on its fancy panel as well, quoting numbers like 108.6%, or even 111.8% coverage of the DCI-P3 color space, depending on which version of the press materials you choose to believe. Also, deltaE values lower than 1.

While the display on the ROG Phone II is indeed incredibly accurate under the "Standard" display mode, we didn't really match the quoted deltaE number. Even so, a max deltaE of 2.2 and an average of 1.3 are perfect even for professional color work. So, we won't hold too much of a grudge.

There are quite a few other built-in display modes to choose from as well. The default "Optimal" setting strikes a nice balance and is great for showing off the "punchy" nature of OLED displays. "Natural" tents to warm the image up a bit, taking away too harsh blues and ramping up greens and reds. "Cinematic" pretty much keeps the same color profile as "Natural", but takes color intensity down all around.

Speaking of colors, we also can't fail to mention that the ROG Phone II's display is true 10-bit, rather than 8-bit with FRC. The actual perceivable difference might be minute, but this is yet another instance of top-level hardware for the best possible gaming experience. Naturally, that means HDR support as well. Just like last year, however, Asus is not openly sharing any particular certification (Dolby Vision, HDR10+ and the like). Still, both Netflix and Amazon video were perfectly happy serving us up their HDR video streams and these looked great on the ROG Phone II.

Asus has also promised a pair of visual optimization modes will be part of a future software update - Contrast Enhancement mode and an SDR-to-HDR converter. Unfortunately, we can't test either at this time.

The ROG Phone II is no slouch when it comes to brightness and contrast. Asus claims it can reach 600 nits outdoors, which is definitely true. In fact, we measured a max auto boost brightness of 626 nits with our standard test that shines 75% of the display. Without any extreme external light sources, you can expect the brightness slider at 100% to give you around 480 nits, which is still a great result.

Speaking of the brightness slider, the ROG Phone II has a really odd one. Pretty much every mobile slider is non-linear by nature. However, most tend to space things out a bit more. On our review unit, the 200 nit brightness level we use for our battery test ended up at 85% on the brightness slider. That leaves 250 or so nits crammed up in just 15% of the slider. Not a major deal, but still worth mentioning.

Touch latency is another area where Asus has clearly spent a lot of time and effort. It is only logical, seeing how important it is as part of the input lag chain for gaming performance.

A high refresh rate display also demands faster input polling. On the ROG Phone II it is set at an impressive 240Hz. But, the engineering team didn't just slap on a fast digitizer and leave it at that. They also optimized the rest of the touch data pipeline from hardware to software, tweaking the Android Framework. As per their own in-house metrics this resulted in a whopping touch latency of just 49ms. Industry leading, in fact, if we are to believe the rest of the numbers Asus quoted for a few of its competitors: iPhone XS Max - 75ms, Xiaomi Black Shark 2 - 82ms, OnePlus 7 Pro - 85ms, Samsung Galaxy S10+ - 87ms.

Rounding the display section off, we feel like we need to reiterate certain concious design choices and how they came about. Asus remains firm in its assessment and commitment to mobile gamer needs. The average "prosumer" or ROG gamer allegedly wants the biggest display feasible, which is how the 6.6-inch diagonal came about. The panel needs to be easy to handle as well, which is part of the reason for the thicker bezels and the lack of curves. The 19.5:9 aspect ratio apparently hits a pretty nice "sweet spot" as far as mobile game engine tech and optimization goes.

The same rational can also be used to explain the FullHD resolution. Of course, there are many other technological limitations at play as well. Plus, the simple fact that driving demanding games at 4K or QHD in high refresh rate is not really within reach for current generation mobile GPUs. Still, if we had to point out a single downside of the magnificent ROG Phone II display it would have to be the resolution.

Battery Life

One pretty major aspect of the ROG Phone II that seems to take a little bit of a back seat, overshadowed by its other features is the enormous 6,000 mAh battery. Seeing how portable power is vital for an on-the-go gaming experience, Asus paid plenty of attention to in. In more ways that one, in fact. Beyond its sheer capacity, which is advertised as lasting 35% longer than other gaming phones under the same gaming load, there are also a few other bits and pieces worth mentioning.

Before that, though, lets get the numbers of out of the way. We ran the ROG Phone II through our standard battery test routine quite a few times, just to cover all scenarios and validate the results. Turns out that running X Mode does not intrinsically increase battery consumption in any meaningful way in the absence of a load. That is kind of logical, since all X Mode does is adjust maximum thresholds for various things, but we still had to check. What does make a noticeable difference in on-screen tests is display refresh rate.

Set at the lowest 60Hz, the ROG Phone II manages pretty solid on-screen scores. It is worth keeping in mind that 6.59" AMOLED panel is still pretty huge.

Even at its maximum 120Hz refresh rate, the ROG Phone II still holds its own in on-screen tests. Looking at the difference in numbers, our web browser test clearly seems less affected by the change in refresh rate. Asus has no intelligent system in place to detect things like a 30fps video being played back and have the refresh rate automatically lowered to save battery. That might be a good idea for a future update, since it does make a difference.

As for 3G talk time and standby - both were understandably excellent on the 6,000 mAh ROG Phone II. Overall, it is one of the top battery champions we have ever tested at the office. And it kind of has to be when you consider its intended typical use case - extended periods of high performance load and increased heat with what will likely be frequent top-offs and prolonged periods of stressful usage while tethered to the wall for power. Generally speaking, this is the worst kind of abuse you can inflict on any Li-Ion pack. Frequent charge cycles, a lot of heat, spending a lot of time at full charge.

However, to Asus's credit, all of this does appear to have been taken into consideration while designing the ROG Phone II. For one, simply having a larger battery pack means less recharge cycles. Plus, ROG claims its ROG Kernel Optimization feature can save up to 180mA per hour of gaming, allegedly resulting in over seven hours of gameplay in PUBG and Arena of Valor on a single charge.

Then there is the question of charging - an area where Asus has also clearly made quite a few proactive decisions. Most notably, it's the choice to skip on the modern trend of pushing extremely fast charging speeds. On one hand, that saves room within the battery itself due to the smaller separator between the anode and the cathode. Also, slower charging is generally better for the battery itself.

Asus' own HYPERCHARGE technology is also pretty sparing when it comes to heat generation. It actually has all the necessary conversion circuitry within the power brick itself, instead of the phone. That means even less heat while charging. The bundled charger itself is rated at 30W, but it should be noted that the phone can only take a 25W current. The other 5W are a convenient overhead for powering any attached accessories. HYPERCHARGE also works with any good quality 3A Type-C to Type-C cable and does not require a more expensive 5A one.

As a fallback, the ROG Phone II also supports Quick Charge 4.0. As for the power brick, it can also output a PD current making it really versatile for charging other devices.

Asus is also taking steps to ensure the health and longevity of its battery pack. In addition to all the hardware steps discussed so far there is also the built-in PowerMaster feature. It works kind of similar to Qnovo, albeit a bit simpler and prevents against a constant prolonged trickle-charge overnight while the phone is already at 100%. It is basically a charging scheduler which makes sure the phone will not fully charge until the user is ready to unplug it.

Speaker test (NEW)

Already familiar with the ROG Phone II's truly impressive speaker setup, you shouldn't be surprised that it aced our new test as well. Its Outdoor mode loudness is miles ahead of anything else we've seen on the revamped test bench, but it's also comfortably louder in regular, non-outdoor mode as well. As such, it's the only phone with an 'Excellent' rating for the time being.

Use the Playback controls to listen to the phone sample recordings (best use headphones). We measure the average loudness of the speakers in LUFS. A lower absolute value means a louder sound. A look at the frequency response chart will tell you how far off the ideal "0db" flat line is the reproduction of the bass, treble, and mid frequencies. You can add more phones to compare how they differ. The scores and ratings are not comparable with our older loudspeaker test. Learn more about how we test here.

Speaker test (OLD)

Audio is definitely an essential part of the gaming experience. Hence, it gets plenty of attention from the Asus design and engineering team. Those two fairly wide areas on top and bottom of the ROG Phone's display house what might very well be the most impressive pair of smartphone speakers we have heard. Failing that, they are definitely somewhere in the Top 5.

Each of these uses a 5 magnet design and gets its own dedicated Smart NXP amplifier. This results in some impressive loudness numbers. So much so that you might rarely find yourself actually cranking the volume to the max. Which would frankly be a shame, since the ROG Phone II is not only loud enough to punch through a hall of talking people, but also do so with impressive depth and clarity.

Seriously, we don't know if we need to praise the DTS:X Ultra tech alone for this accomplishment, but the ROG Phone II has an amazing sound stage. You actually feel the bass while holding the phone and best we can tell it's not the vibration motors contributing to the effect, like certain Xperia phones try to do. The speakers simply resonate, as it should be. Mids also come out very rich and full and highs remain crisp.

AudioWizard

You also get quite a few equalizer options in the settings menu, including an Outdoors mode. The latter seems to boost the average volume even more, but also pushes down lows and mids and brings up higs to almost unpleasantly squeaking levels. We don't particularly like what it does to the otherwise splendid sound stage, but to Asus' credit it does result in an even more piercing and permeating sound - assuming it's really needed.

Audio quality

The Asus ROG Phone II put in a stellar performance in our test, demonstrating super loud output both with an external amplifier and with headphones. The clarity was impressive too - perfect in the first case and almost as good in the second one.

Even the expected drop in stereo separation is much smaller compared to most other phones out there and certainly makes the ROG Phone II one of the best performers in the market ever.

Asus ROG Phone II frequency response

You can learn more about the tested parameters and the whole testing process here.