Flashback: breaking through the 60Hz barrier
Have you ever wondered why 60Hz is the default refresh rate for monitors? It started with analogue TVs, then their CRT tubes were transformed into computer monitors. Then came LCD monitors, but their slow response times meant they couldn’t really get above 60Hz. Plus, 60Hz was good enough, right?
As PCs became more powerful, they began playing videos – videos shot and edited using TV equipment, so 60Hz (interlaced, but let’s stay out of that rabbit hole). Fast forward to today, 60Hz is still seen as the “normal” refresh rate, but high refresh rate (HRR) displays are becoming more and more common on smartphones to the point where they’re expected on anything above entry-level.
So today’s story starts in 2017 with the Razer Phone. The providers of RGB-charged gaming hardware had acquired Nextbit a few months earlier. For those who don’t remember, the company was known for the Nextbit Robin, a “cloud-first” smartphone that only came with 32GB of built-in storage and no microSD slot – you were expected to use 100GB of cloud storage for files. If we’re being kind, we could say that the idea was ahead of its time for 2015. Fortunately, the Razer Phone did away with the cloud-first approach – it had 64GB of storage and a microSD slot, it was groundbreaking in other ways.
The Razer Phone was equipped with a 5.7″ IGZO IPS LCD that was quite a sight when we first saw it in late 2017. This Sharp-made panel ran at 120Hz, double the refresh rate of other phones on that time.
Even better, the panel got it right out of the gate and supported variable refresh rate (VRR). This allowed the display to adapt to the refresh rate that the GPU could handle, resulting in a smooth, tear-free experience. As powerful as the Adreno 540 inside the Snapdragon 835 was, it couldn’t really keep the FPS stuck at 120. And it didn’t need to.
Incidentally, this was a 1440p display, sharper than some flagship displays today. And it supported a wide color gamut, something that was just starting to gain traction at the time. The cherry on top were the front-facing stereo speakers that flanked the display – this was a gaming and multimedia phone, and it let everyone know.
As is often the case, Sharp was an early adopter of new technology (its own technology in this case). The Sharp Aquos R Compact was announced in October 2017 with a 4.9″ 1080p 120Hz display. Sharp had supplied HRR displays to other manufacturers even before that, but none as well known as Razer.
The following year, Razer came out with the second-generation handset, the Razor Phone 2, although it appears to have used the same panel, just switched from Gorilla Glass 3 to GG5. The Razer logo on the back now had RGB lighting, which means something to that particular fanbase.
Asus joined the game with the original Asus ROG Phone, but it took a different approach. It opted for an AMOLED panel with a 90Hz refresh rate – but not a variable refresh rate. And it had a lower resolution, 1080p (which was probably more realistic given the capabilities of the Snapdragon 845 GPU).
Razer Phone 2 • Asus ROG Phone ZS600KL • Sharp Aquos R2 compact
2019 was when high refresh rate displays became mainstream – the Pixel 4 series had it, the OnePlus 7 series had it, as did the Oppo Reno3 Pro, Realme X2 Pro, Redmi K30, a Lenovo Z6 to name a few. A relatively fresh gaming phone series from ZTE, Red Magic, also introduced its first HRR phones that year.
Google Pixel 4 • OnePlus 7 Pro • Oppo Reno3 Pro 5G • Realme X2 Pro
Xiaomi Redmi K30 5G • Lenovo Z6 • ZTE nubia Red Magic 3 • Asus ROG Phone II ZS660KL
Most of these phones used AMOLED screens, although the Redmi K30 had an LCD. And they had one thing in common – they lacked variable refresh rate support. This was something only phones equipped with IGZO panels could do at the time, and seeing how Razer had given up on the phone business, that only meant the occasional Sharp Aquos.
It took a while for VRR to return to smartphones, and it came when LTPO AMOLED panels started coming out of the factory. These were shown on several 2021 models from the usual suspects – Google, OnePlus, Oppo and Xiaomi, plus some vivo models.
Google Pixel 6 Pro • OnePlus 9 Pro • Oppo Find X3 Pro
Xiaomi 12 Pro • vivo iQOO 8 Pro • Apple iPhone 13 Pro Max
It is possible to do VRR on non-LTPO displays, it’s just not efficient. In fact, it was the original use case for the technology (Apple used it on the Apple Watch Series 4). Apple finally joined the HRR party with the iPhone 13 series last year, despite offering iPads with ProMotion displays (starting with the second-generation iPad Pro).
As we said earlier, an HRR screen is something that is taken for granted on modern mid-rangers and especially for flagships, where 120Hz is the most common figure, although there are a few 90Hz models out there as well.
Mostly, it’s gaming phones that push higher. The Red Magic 5G was the first to reach 144Hz in March 2020, then the Red Magic 6 reached 165Hz a year later, which is as high as smartphones have gotten for now.
ZTE nubia Red Magic 5G • ZTE nubia Red Magic 6
Gaming monitors and laptops now offer 240Hz, 300Hz, 360Hz and so on, so we have no doubt that sooner or later some gaming phones will get above 165Hz. Whether that’s actually useful with a battery-powered GPU is another question.
When it comes to refresh rate, the phone’s interface is noticeably smoother at 90Hz, more so at 120Hz, and then things start to fall off. Gaming phones want the lowest possible latency to give gamers better response times, so for them it makes sense to go for higher refresh rates.
For general smartphone use, however, we’re guessing 120Hz will be the norm for several years. We believe that the focus will be on other improvements, e.g. a wider use of variable refresh rate panels (which really helps with Always On Displays, but also with gaming).