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Given that Samsung has running promos for the Galaxy S21 Ultra that bring its starting price down to a grand, while OnePlus issued its first $999 phone last year, the OnePlus 8 Pro, it doesn't seem illogical to compare the upcoming OnePlus 9 Pro with Samsung's finest for the season any more.
Big 6.7"/6.8" display phones can't be compact, and the OnePlus 9 Pro as well as the Galaxy S21 Ultra can't be an exception. Moreover, the premium glass housings add to the weight and bulkiness, making them very uncomfortable to carry around and use with one hand. That being said, the OnePlus 9 Pro is quite a bit lighter and more compact in all dimensions, so it feels slightly more palm-friendly.
OnePlus 9 Pro vs Samsung Galaxy S21 size and design
From the back, the phones don't look all that different, camera island at the top left corner and all, Samsung's Infinity-O design moved the punch hole for the front camera in the middle of the display, while OnePlus 9 Pro keeps it at the top left corner. The OnePlus mute switch is, naturally, present to set the buttons of the 9 Pro apart from the Ultra.
The CIE 1931 xy color gamut chart represents the set (area) of colors that a display can reproduce, with the sRGB colorspace (the highlighted triangle) serving as reference. The chart also provides a visual representation of a display's color accuracy. The small squares across the boundaries of the triangle are the reference points for the various colors, while the small dots are the actual measurements. Ideally, each dot should be positioned on top of its respective square. The 'x: CIE31' and 'y: CIE31' values in the table below the chart indicate the position of each measurement on the chart. 'Y' shows the luminance (in nits) of each measured color, while 'Target Y' is the desired luminance level for that color. Finally, 'ΔE 2000' is the Delta E value of the measured color. Delta E values of below 2 are ideal.
The Color accuracy chart gives an idea of how close a display's measured colors are to their referential values. The first line holds the measured (actual) colors, while the second line holds the reference (target) colors. The closer the actual colors are to the target ones, the better.
The Grayscale accuracy chart shows whether a display has a correct white balance (balance between red, green and blue) across different levels of grey (from dark to bright). The closer the Actual colors are to the Target ones, the better.
Well, we are happy to report that we have a new "best mobile display" crown in the OnePlus 9 Pro. How did it beat the 6.8" LTPO panel of the S21 Ultra that can reach record brightness, and offers granular 10Hz-120Hz refresh rate at the full display resolution, as well as HDR10+ support? Well, all of that, plus even lower, 1Hz-120Hz variable refresh range, and a Pixelworks X5 Pro visual processor that works together with the camera and CPU to enhance the visuals real time, say Pixelworks, and we are happy to report that the panel is indeed the best mobile display so far:
Enhanced by the Pixelworks X5 Pro processor, the new flagship OnePlus 9 Pro smartphone integrates a 6.7” cutting edge Fluid LTPO AMOLED display with WQHD+ resolution and variable refresh rates up to 120 Hz.... Whether viewing pictures and videos captured using the phone’s Hasselblad camera or streaming content or short videos, Pixelworks visual processing technologies are designed to deliver perfect color reproduction, superior display quality and eye comfort in all kinds of ambient lighting conditions.
One thing the 9 Pro won't be able to replicate, though - the active S Pen digitizer that the S21 Ultra has. Granted, it comes with a case that tacked on makes the phone even bigger, but that's the price to pay for the doodling streak in you.
OnePlus 9 Pro vs Samsung Galaxy S21 Ultra specs, performance and battery life
The beasts of a phone are only separated by the amount of RAM and storage they will be available in, as the Snapdragon 888 and its integrated X60 modem come standard. The OnePlus 8 Pro starts with 8GB RAM/128GB ROM version, whereas the S21 Ultra keeps it real with 12GB RAM, all the way to a 16GB RAM/512GB model that is so in vogue that it's currently sold out over at Samsung.
If the T-Rex HD component of GFXBench is demanding, then the Manhattan test is downright gruelling. It's a GPU-centric test that simulates an extremely graphically intensive gaming environment that is meant to push the GPU to the max. that simulates a graphically-intensive gaming environment on the screen. The results achieved are measured in frames per second, with more frames being better.
AnTuTu is a multi-layered, comprehensive mobile benchmark app that assesses various aspects of a device, including CPU, GPU, RAM, I/O, and UX performance. A higher score means an overall faster device.
The 4500mAh battery in the OnePlus 9 Pro can't be a match for the huge 5000mAh unit in the Galaxy S21 Ultra but last year the OnePlus 8 Pro scored extremely well on our battery life tests, even in the demanding 3D gaming endurance benchmark. Thus, we kept our hopes high that the best-in-class Galaxy S21 Ultra battery life performance in our database can be replicated by OnePlus, frugal LTPO display and everything. Unfortunately, the larger battery of the S21 Ultra played its part, and the OnePlus phone showed shorter endurance than Samsung's finest.
On the other hand, the 65W charger that the OnePlus 8T shipped with, stays in the OnePlus 9 Pro box as well, and now charges for the breathtaking 29 minutes, way faster than the not-slouchy S21 Ultra. There is a "one more thing," too, in the form of a 50W wireless charging support that takes the unit to 100% for 40 minutes, so the battery round is not the easy win for Samsung as it looks from the tests here.
OnePlus 9 Pro vs Samsung Galaxy S21 Ultra camera comparison
The OnePlus 8 Pro camera specs are a bit contradictory - it sports a 48MP main camera plus monochrome and 3x zoom units but also a new 50MP sensor which makes a cameo in the OnePlus 9 as well. Compare that to the 108MP main beast and 10x periscope zoom of the S21 Ultra, and you'll see how the flagships stack up in the camera hardware department - the 9 Pro has only the ultrawide camera advantage.
Thankfully, OnePlus stepped up the 9 series camera effort and it is the best thing that has happened to the company's phone cameras in a while. It intends to plow $150 million in the span of three years in camera hardware and software in partnership with the storied camera company Hasselblad. Yes, that's the one used to shoot the Earth after the lunar landing.
As you can see, while the 8-series demonstrated that OnePlus can finally create pretty decent camera kits, and we see that the 9 Pro performs well, the monstrous camera set on the S21 Ultra, however - 108MP main sensor plus 10x/3x optical zoom cameras - is hard to beat for any current phone, not just the 9 Pro.
Perhaps save for the excellent 50MP ultrawide Sony camera with freeform lens on the 9 Pro, and some macro shots, the Galaxy S21 Ultra excels in detail, dynamic range, low-light sharpness, selfie and portrait capture, as well as cleaner zoom levels. Thus, if you meet Samsung's flagship at a price close to the 9 Pro, it's a no brainer given that the display is almost as good, and the battery life way better, too.