In 2014 OnePlus was a company that was basically unheard of. Despite that, there was great anticipation in the Android enthusiast community about a new smartphone coming from this new company. Their first smartphone ended up being called the OnePlus One, and it was arguably the first device in a trend of smartphones that tried to bring flagship specifications to devices with prices much lower than what the big players in the smartphone market demanded for their best smartphones. The OnePlus One certainly wasn't perfect, but it showed that it was possible to produce a high spec smartphone for hundreds of dollars less than Android flagships, and what OnePlus needed to improve on was their execution.

A year came and went, and OnePlus came out with the OnePlus 2. This was during a time where the Android market was still struggling to deal with the issues posed by Qualcomm's Snapdragon 808 and 810 SoCs, which put Android performance improvements at something of a standstill. In the case of the OnePlus 2, I discovered that OnePlus had put mechanisms in place that reduced web performance even further, and as I reviewed the OnePlus 2 I discovered concerning regressions in other aspects like the phone's display, and its battery life.

Moving into 2016, we now have the OnePlus 3. At this point OnePlus now has a better variety of hardware to choose from, and they should know exactly what to fix from the OnePlus 2 to make a great smartphone. However, the smartphone market gets more competitive with each year that passes, and it's no longer enough to simply put good specs in a device and fail with the execution. Finding out how well OnePlus executed with the user experience is what I'm here to tell you, but before getting in to that, it's important to see how the OnePlus 3 compares to its predecessor.

	OnePlus 2	OnePlus 3
SoC	Qualcomm Snapdragon 810	Qualcomm Snapdragon 820
GPU	Adreno 430	Adreno 530
RAM	2/4GB LPDDR4	6GB LPDDR4
Display	5.5" 1920 x 1080 IPS LCD	5.5" 1920 x 1080 PenTile AMOLED
Size / Mass	151.8 x 74.9 x 9.85mm, 175g	152.7 x 74.7 x 7.35mm, 158g
Battery	3300 mAh	3000 mAh
Rear Camera	13MP 1.3 μm OmniVision OV13860 f/2.0	16MP 1.1 μm Sony IMX298, f/2.0, OIS
Front Camera	5MP 1.4 μm OmniVision OV5648, f/2.0	8MP 1.4 μm Sony IMX179, f/2.0
Storage	16/64GB eMMC	64GB UFS 2.0
I/O	USB 2.0 Type-C connector, 3.5mm audio
Connectivity	802.11a/b/g/n/ac + BT 4.1 USB-C, GPS/GNSS	802.11a/b/g/n/ac + BT 4.2, USB-C NFC, GPS/GNSS
Price	$329 (3GB/16GB) $389 (4GB/64GB)	$399 (6GB/64GB)

At least at a high level, the OnePlus 3 shows a great deal of promise. The move from Snapdragon 810 to 820 will certainly improve performance, especially when you consider the app detection that OnePlus was doing which crippled web performance on the OnePlus 2. There's also a whopping 6GB of RAM. I do wonder if 6GB is overkill only because the number of apps that people actually use on a daily basis may be smaller than the number that 6GB can actually keep resident in memory. It's also worth noting that there is an energy cost to adding more RAM as each memory cell has to be periodically refreshed to maintain data integrity.

OnePlus has moved to an AMOLED display with the OnePlus 3. While it was once the case that AMOLED displays that weren't on Samsung devices exhibited low brightness and poor calibration, recent AMOLED devices have reversed that trend entirely. However, moving from a 1080p RGB LCD to a 1080p PenTile AMOLED does come with a reduction in effective resolution, and I'll talk about that more in the display section.

With the cameras, OnePlus has gone back to Sony sensors. The front-facing camera moves to 8MP, and the rear-facing goes to 16MP. Lenses stay at f/2.0 which I think is a smart move given some of the problems we've seen regarding sharpness and distortion on phones that have moved to even wider apertures. There's more to the camera story than what you see on paper, and I'll be covering that as well.

As for other changes, there's now only one version of the phone which is 6GB of RAM and 64GB of UFS 2.0 storage for $399. I almost never saw the 16GB OnePlus 2 for sale anyway, so this isn't really some sort of pricing upset. As for connectivity, you still have a USB 2.0 based Type-C connector and 802.11ac WiFi, but NFC has made a return which means the OnePlus 3 will be usable with Android Pay and other applications that make use of NFC.

Design

One of the big changes OnePlus has made with the OnePlus 3 is the industrial design. Nothing about the OnePlus One's design was really exceptional, but given that it was bringing many flagship specs to a phone that costed several hundred dollars less than flagship phones of the time it was entirely understandable. With the OnePlus 2 the average price of OnePlus's flagship phone went up, but OnePlus had made some changes to the external design. The phone gained a metal frame but retained its sandstone back cover. To be honest, I wasn't really a fan of the OnePlus 2's design. The metal frame didn't do much to improve how high quality the phone felt, and the back cover wasn't coarse enough to really have an impact on how grippy the chassis was. On top of that, the fact that the display layer of the phone had a plastic border that sat above the metal frame looked kind of cheap, and the increased thickness and mass actually represented regressions from the OnePlus One in some respects. 

With the OnePlus 3, OnePlus has moved to an aluminum unibody design. In doing so they've addressed pretty much all of my issues with the OnePlus 2. Starting with the back of the device, you no longer have the sandstone finish. I'm sure many people will disagree, but the OnePlus 2 back cover didn't help me with gripping the phone at all. The OnePlus 3 feels like a much higher quality device, particularly because there are no longer three distinct sections of the phone that all have seams and gaps between one another. The unibody design means the back cover is no longer removable, but as I said in my OnePlus 2 review I think the removable back cover on OnePlus devices was a complete waste anyway because it only served as a way to access the SIM slots, which could have been implemented as a tray on the side of the device. With the OnePlus 3 they've done exactly that, and so the removable back cover isn't needed.

The back cover sees some additional changes, with some being independent of the move to an aluminum chassis. There are now lines for the antennas on the top and bottom of the phone, and the top line connects to the square-shaped camera sitting beneath it, which reminds me of the HTC One M9. On the topic of the camera, there's no longer a separate island that the camera and flash sit upon, which I think is a big improvement on what I felt was one of the least appealing visual aspects of the previous OnePlus devices. The camera does stick out significantly more than it did on the OnePlus 2 which is just a consequence of the significant reduction in thickness, and OnePlus has actually decreased sensor size with this generation so the hump likely would have been even larger if they hadn't. The only other thing to note about the camera area is that there's now just a single LED flash and the camera uses PDAF, while the OnePlus 2 had a dual LED module and an IR module for the laser autofocus.

On the left side of the phone you have the volume rocker and the mute switch, while the right side has the sleep/wake button and the NanoSIM slots. I appreciate that OnePlus has kept their volume rocker on the left side of the phone, and I think the three stage mute switch is an underappreciated feature that more manufacturers should adopt. You can see above that the phone's edges only curve to a point, at which point you have a chamfered edge that meets the display glass. I like the appearance that this provides, but it does mean that you don't have the same smooth feeling when swiping near the edges of the display that you get on a device like the iPhone 6s Plus. 

The bottom of the phone is changed from the OnePlus 2. There are no longer any antenna lines since they wrap around the left and right sides of the phone, and there aren't holes drilled on both sides of the USB Type-C port which has allowed the 3.5mm audio jack to be brought to the bottom of the phone. One thing that bothers me is how the 3.5mm jack isn't centered like the rest of the ports and screws, which kind of ruins the visual uniformity. You can also see OnePlus's pre-applied screen protector in the image above. It doesn't quite cover the entire display from edge to edge, and I noticed that a great deal of dust was collecting around the edges so I ended up removing it. It's just your typical plastic screen protector rather than a glass one anyway, although the fact that OnePlus throws it in for free is a nice gesture.

The front of the phone is similar to the OnePlus 2, but it's clear how the overall shape of the phone has changed to become more curved, while the OnePlus 2 was similar to the Nexus 5 in how it had flat sides meeting curved ones at hard angles. I have to say that I prefer the appearance of the OnePlus 3 in this regard, but it may be seen as less unique than the OnePlus 2. As for what's on the front cover, you have the earpiece and front-facing camera on the top, with three capacitive keys on the bottom. The middle key is the home button, which also acts as a fingerprint scanner in the same manner as the OnePlus 2's home key. In my experience the sensor has been quite accurate and just as quick as anything else on the market, and having it on the front of the device provides a better experience than rear-mounted scanners.

OxygenOS provides many ways to customize the phone, so you also have the option to switch the order of the back and recent apps buttons, and if you want software keys OnePlus provides that as an option as well. I covered the major points of OxygenOS in my OnePlus 2 review, and I haven't seen any major changes to it so I'll just refer to that rather than going over the features a second time. The one thing that has changed is that the UI no longer feels unbearably slow and sluggish, and in the next section you'll see exactly why that is.

System Performance

2015 was not a great year for Android devices. Snapdragon 810’s problems with throttling severely crippled the performance of high end smartphones. In the case of the OnePlus 2, OnePlus went even farther by putting in code that would detect when Google Chrome was in use and completely shut off the A57 cluster on the SoC. This resulted in web browsing performance that was essentially no better than what you’d find on a $100 phone shipping with Snapdragon 410, which simply wasn’t acceptable given the fact that the OnePlus 2 was priced at around $400.

Like most of this year’s flagship Android devices, the OnePlus 3 uses Qualcomm’s Snapdragon 820 SoC. We looked at Snapdragon 820 not long ago in the LG G5 review and saw that it provided a substantial improvement over Snapdragon 810, which became even greater when you consider prolonged workloads where Snapdragon 810’s A57 cores throttle down and shut off. Given that OnePlus no longer has any reason to put in strange app detection code to manage thermals, we should see a good uplift in general performance and an enormous improvement in web performance.

The improvement in web browsing performance when going from the OnePlus 2 to the OnePlus 3 is staggering. This isn't unexpected when you consider that the OnePlus 2 was just running on Cortex A53 cores that were meant for low power scenarios while the OnePlus 3 is using Qualcomm's Kryo cores. In Kraken the OnePlus 3 is over four times faster, while in WebXPRT and JetStream it's at least over two times faster. The OnePlus 2 actually represented a large regression in web performance compared to its predecessor, and OnePlus has brought web performance back to a level that is competitive with the other smartphones on the market with the OnePlus 3.

PCMark is an interesting test because it depends just as much on a phone's software as it does on the hardware. We've seen how devices with the same SoC can perform very differently, especially in certain sub-tests like the Writing and Photo Editing tests where different runtime and OS optimizations can have a large impact. The OnePlus 3 is no exception, with it achieving higher scores than the LG G5 in every test except for video playback where they have roughly the same scores.

This is not unexpected, as it was demonstrated in the LG G5 review that the G5 has more conservative frequency scaling than the other Snapdragon 820 devices that we've seen, which is reflected in PCMark's tests. In any case, the OnePlus 3 actually gets close to the Huawei Mate 8 in the writing test, and beats it and the LG G5 by a large margin in the photo editing test. In the end the OnePlus 3 places second on our overall chart, with only the Huawei Mate 8 ahead of it, and the gap between it and the Mate 8 being smaller than the gap between it and the Zenfone 2 which is the next fastest smartphone.

The OnePlus 3 is over two times faster than the OnePlus 2 with cold app launches where the application isn't resident in memory in any state. This is likely a combination of improved NAND performance, and changes to OnePlus's DVFS settings in addition to the performance improvements that Snapdragon 820 provides on its own. The impact that this has on the performance of the interface is significant, and when I reviewed the OnePlus 2 I noted how painfully slow it was to move around and through the applications. This new testing is a great example of that, with the OnePlus 2 taking 1.3 seconds just to launch apps, while the OnePlus 3 takes under 500ms and is the second fastest device here.

The OnePlus 3 improves a bit over the OnePlus 2 when resuming apps that are resident in memory, but not by a great deal. In general, all our devices hover between 250 and 300ms here, with the exception of the Huawei Mate 8 and P9 which are really in a category of their own for performance. While there's no enormous improvement here, the OnePlus 3 is competitive with other high end devices in the market, so there's nothing to complain about either.

One thing worth noting is that our set of apps wouldn't come close to utilizing the OnePlus 3's 6GB of RAM. Unfortunately, no matter how many apps we added, this would actually still be the case. The reason is that OnePlus has implemented very aggressive app eviction from memory, which means that your 6GB of RAM is really just sitting there using energy, and in general the utilization is pretty low. This may be a holdover from when the OnePlus 2 shipped in a 3GB configuration, but it's something OnePlus needs to address in a future OTA update. I'd imagine the Android enthusiast community is already at work on, or has already created custom kernels to alter this behavior as well. With 6GB of RAM you should be able to comfortably keep all of a user's frequently used apps resident in memory.

It's great to see that OnePlus is producing a smartphone with competitive performance once again. When the OnePlus One launched, Snapdragon 801 was the best you could get in an Android smartphone. The OnePlus 2 was an unfortunate victim of Snapdragon 810's heat and throttling problems, but OnePlus certainly didn't help the issue by hardcoding in mechanisms to detect Google Chrome and shut the A57 cluster off entirely. With the OnePlus 3 you get some of the best CPU performance in an Android phone, with PCMark's real-world tests demonstrating noticeable gains over the LG G5 which also uses Snapdragon 820. If I had to sum things up in a single line I'd just say that it's good to see that OnePlus is back in the game.

GPU Performance

GPU performance is one of the areas where Snapdragon 810 actually tended to do quite well. It's also the case that GPUs generally see larger performance gains year over year than CPUs. We already saw how Adreno 530 performs in the LG G5 review, but the device being compared to was the LG G4, which used Snapdragon 808. The OnePlus 3 represents an opportunity to compare a Snapdragon 810 device to its successor using Snapdragon 820.

The OnePlus 3 does very well in 3DMark Sling Shot. In both the physics and graphics tests it trails the LG G5 slightly, but the gap isn't anything truly significant. Exynos 8890 is still not something I can compare to until our Galaxy S7 review is posted, but barring that it's clear that Snapdragon 820's Adreno 530 gives the fastest smartphone performance in this test, and when looking at the graphics performance the performance is over two times faster than the OnePlus 2.

In BaseMark ES 3.1's on screen test the OnePlus 3 manages a significant lead over the LG G5 as a result of its lower resolution. In the off screen 1080p test both phones have essentially the same performance, which is what you'd expect. It looks like Adreno 530 doesn't make the same gains in this test that it does in some others, and it's not clear whether this is just the result of driver optimizations or something about the benchmark that is able to perform batter on other GPU architectures, which could be contributing to the iPhone's lead even in the off screen test.

In GFXBench Car Chase the performance of the OnePlus 3 is in line with the LG G5. On screen performance is significantly higher due to the lower resolution display, while off screen performance at 1080p is about the same as the G5 and exactly the same as the on screen result. As far as absolute GPU performance goes, both of our Snapdragon 820 devices are at the top of the chart for absolute performance, and that's good news for anyone playing games or using software that benefits from a powerful mobile GPU.

NAND Performance

The OnePlus 3 moves to a UFS 2.0 NAND solution, which OnePlus claims is three times faster than the eMMC storage used in the OnePlus 2. In more realistic testing you probably won't end up achieving speeds three times faster than the OnePlus 2 since it actually wasn't slow at all by eMMC standards, but there should be a decent uplift in NAND performance nonetheless.

The move to UFS 2.0 brings healthy gains over the OnePlus 2's storage performance, although as I said, the OnePlus 2 didn't perform poorly at all by the standards of eMMC devices. Sequential read and write performance is actually the best that I've measured so far on an Android device. We're still not looking at anything close to what you get for sequential performance on iOS devices, but there are some other factors at play like the fact that the iPhone was a 128GB unit while our Android devices are usually 32GB or 64GB devices. In any case, the OnePlus 3 doesn't present any problems with storage performance, and you certainly won't run into the same issues that you can with budget smartphones at the $200-300 range where the eMMC solutions can be exceptionally slow.

Display

Update: OnePlus has since addressed the issues with calibration. Click here for my follow-up article.

One of the most disappointing aspects of the OnePlus 2 was its display. Like the OnePlus One it was a 5.5” IPS LCD display, but the similarities ended there. The OnePlus One shipped with a very well calibrated display, and at the time that wasn’t something you could always expect from devices priced around $300. With the OnePlus 2 the display got a much appreciated boost in peak brightness, but the color accuracy regressed severely. The display was heavily blue shifted, and to say that it tied the Nexus 6 as the most inaccurate display tested in recent years would actually be generous. With how good the display on the OnePlus One was, the OnePlus 2 was a huge letdown.

The OnePlus 3 is a chance for OnePlus to fix the mistakes they made with the OnePlus 2. Like the past two OnePlus flagship devices, we’re still talking about a 5.5” display. However, OnePlus has moved to an AMOLED panel. OnePlus calls this an Optic AMOLED display, although they don’t go into much detail on what that means, beyond claiming that the display uses “Custom-engineered gamma corrections that help create a more natural viewing experience”. It’s generally not a good sign when the description of a technology is very vague and just throws in some technical jargon instead of quantifying and explaining what is actually going on. OnePlus also claims that the display “produces colors that are more vivid and true-to-life than other AMOLED displays”, which sounds like good news given how accurate the AMOLED displays on other smartphones already are.

Before covering display accuracy, I want to comment on OnePlus's use of a 1080p AMOLED panel. According to comments made by OnePlus, a 1080p display was chosen as it provides superior battery life, and because resolutions above 1080p are not useful outside of VR. I have to respectfully disagree with both points, especially because this is a PenTile AMOLED display. It has been well demonstrated that good battery life is achievable not just with 1440p AMOLED smartphones, but with 1440p LCD smartphones. While I do feel 1080p is a good resolution to choose for a 5.5" RGB LCD panel, it is simply not adequate for a PenTile AMOLED display.

When you consider the effective resolution of red and blue on the OnePlus 3, you're really dealing with a display that is roughly equivalent to the iPhone 6s in chroma resolution, except on a 5.5" display instead of a 4.7" one. The resolution for green is equivalent to a 1080p display, and subpixel rendering is what allows you to make the claim that it's still a 1080p display, but for everything except pure green your effective resolution is going to be lower. In addition to that, the uneven size and spacing of the subpixels, along with their diamond pattern, makes them less than optimal for rendering the latin alphabet which contains many vertical lines. This kind of screen door effect has long been noticed on PenTile displays, and for the most part the push for 1440p AMOLED panels has mitigated those complaints.

On the OnePlus 3 it's pretty obvious that text is rendered less clearly than the iPhone 6s, which has a pixel density of only 326ppi, well below that of flagship Android devices. With the OnePlus One and OnePlus 2 for comparison it's completely obvious that the OnePlus 3 has a lower effective resolution, with text exhibiting distracting artifacts, and solid patterns that are red, blue, or white having a crosshatch pattern that simply isn't visible on OnePlus's older smartphones. I completely agreed with OnePlus's choice of 1080p on their past smartphones, but saying that there's no benefit to going higher on a PenTile AMOLED display is simply false, and there's no getting around the fact that the OnePlus 3 has a lower effective resolution than its predecessors. 

While OnePlus isn't off to a great start with their display resolution, there are many other aspects of a display that need to be considered beyond the number of pixels. To examine the OnePlus 3’s display I’ve run our standard display workflow on it. As always, measurements are performed with an i1Pro 2 spectroradiometer, with the exception of contrast which is done with an i1Display Pro colorimeter. Data is collected and managed with SpectraCal’s CalMAN 5 software.

Right out of the gate things are not looking good for the OnePlus 3. Peak brightness only hits 413 nits, which is a huge regression from the OnePlus 2’s 554 nits. The impact that this has on outdoor usability is very significant, with the display being much harder to use in the sun than the OnePlus 2. To make matters worse, there’s no brightness boost mode that activates when you have the auto-brightness on. At this point I really don’t think it’s acceptable to ship a phone that can’t hit 500 nits when you’re in the sun, and Samsung is pushing 600 nits on their AMOLED displays when they boost brightness so OnePlus is well behind the competition.

Given that the OnePlus 3 uses an AMOLED display, you technically have infinite contrast when there’s no ambient light. In practice the OnePlus 3 definitely has better black levels than any LCD device that I own, but the OnePlus 2 still had a great static contrast ratio, and the better blacks weren’t worth sacrificing the 550 nit peak brightness at all.

SpectraCal CalMAN

Greyscale accuracy on the OnePlus 3 is very poor. It’s not as bad as the OnePlus 2, but given how severe the errors are, it’s entirely possible that I just happened to get an exceptionally bad OnePlus 2 unit and an exceptionally good OnePlus 3. Whatever the case may be, the OnePlus 3 still has severe issues with greyscale rendition. Gamma is somewhat more accurate than the OnePlus 2 that I received, but the display has even more severe blue shifting, and it’s immediately apparent right from the very first setup screen when you turn on the phone.

SpectraCal CalMAN

In the saturation sweep test, the OnePlus 3 performs even more poorly than the OnePlus 2. You can tell from the gamut that they’re actually targeting NTSC, which makes me feel like I’ve been sent back in a time machine to 2010 where this was the problem with AMOLED displays on smartphones like the Nexus One and the original Galaxy S. I really thought that we had moved past this, past the point where AMOLED phones would ship with nonsensical gamut targets that you can’t change, but clearly I was wrong.

What I really don’t understand is why the NTSC gamut was chosen as the target. With very old AMOLED phones this was chosen under the mistaken belief that NTSC was the correct gamut to use for displaying videos on smartphones, which was absolutely wrong. The gamut defined in the NTSC standard is over sixty years old, it was never even reproduced properly on the CRT displays of the time because they couldn’t do so with an adequate brightness level, and it was replaced as a “standard” gamut decades ago, basically not ever being used outside the Americas at all. When a smartphone targets Adobe RGB you can at least see the misguided but well-intentioned attempt to give a wider gamut using a color standard that actually is used in some cases, but when NTSC is the target it just shows a severe lack of understanding of modern displays and color standards.

SpectraCal CalMAN

With poor greyscale and color reproduction, there’s absolutely no hope for proper color mixture rendition. As expected, the OnePlus 3 also regresses here, and beats the OnePlus 2 as the most inaccurate display on the chart. I really don’t have anything else to say here, as I’m just so frustrated by OnePlus’s choices here.

It’s evident that OnePlus didn’t learn from the issues I demonstrated with the OnePlus 2’s display. It was a serious regression from the OnePlus One, and with the OnePlus 3 they’ve somehow found a way to regress even further. Of all the aspects of a phone to mess up, the display is the absolute worst. There’s basically no use case where you use a phone without looking at the screen, and right from the very first moment I turned on the OnePlus 3 I could tell that the colors are completely wrong. It’s just a huge disappointment.

There is one glimmer of hope. After reaching out to OnePlus, explaining why the choice of the NTSC color space as a target doesn't make any sense, and showing the errors it causes with sRGB rendition, they told me that they now intend to offer an sRGB mode as an option in an upcoming OTA update. There's no firm timeline for this which makes me uneasy, and I can't make a recommendation based on an update that isn't guaranteed, but it's worth making note of. Unfortunately, I am unsure of whether or not this is something that can be fixed after the phone has already shipped. OnePlus has left the display extremely blue which is often indicative of little or no white point calibration, which would mean it's impossible to tune the phones because you don't even have an idea of what the panel characteristics are. For that reason, I remain hopeful but somewhat skeptical, and I plan to revisit the display of the OnePlus 3 if and when OnePlus adds this feature.

While an sRGB mode may be coming, right now the display accuracy you get on the OnePlus 3 reminds me a great deal of early AMOLED devices from 2010, and that's not a good thing at all. I really expected OnePlus to fix their mistakes from the OnePlus 2 because they did so with so many other aspects of the phone. The only explanation I can think of is that nobody actually understood the negative impact of shipping a wide gamut display on a non-color-managed operating system. This actually seems like the most likely explanation, as the choice of NTSC as the target gamut was definitely not an informed decision. Regardless of what path led to the OnePlus 3's current display, the end result is that the poor display calibration ruins the phone for me, because the screen is just unpleasant to look at. If display accuracy doesn’t matter at all to you it may be possible to overlook it, but for anyone who cares even the slightest bit the issues with the OnePlus 3’s display will be too severe to live with.

Camera Architecture

Camera quality was not one of the OnePlus 2's strong points. OnePlus had made an effort to improve on their almost non-existent processing from the OnePlus One, but they went too far and ended up destroying the detail within images. With the third iteration of their flagship phone they need to find a middle ground between the image processing of the OnePlus One and OnePlus 2. That image processing needs to be built on a solid foundation, and with the OnePlus 3 comes a move away from the OmniVision camera sensors used in the OnePlus 2, along with changes to some key aspects like the autofocus mechanism. The specifications of the OnePlus 3's camera system can be seen below with the OnePlus 2 also there for comparison.

	OnePlus 2	OnePlus 3
Front Camera Resolution	5MP	8MP
Front Camera Sensor	OmniVision OV5648	Sony IMX179
Front Camera Aperture	f/2.0
Rear Camera Resolution	13MP	16MP
Rear Camera Sensor	OmniVision OV13860 (1/2.6")	Sony IMX298 (1/2.8")
Rear Camera Focal Length	28mm eff	29mm eff
Rear Camera Aperture	f/2.0
OIS	Yes
Autofocus	Laser	Phase detection

OnePlus has moved back to Sony sensors with the OnePlus 3. What's interesting is that they've actually moved to a smaller sensor size, which was probably a combination of what was available within pricing constraints, as well as how thin the sensor needed to be to minimize the camera hump on the back of the phone. In addition to the sensor shrinking, the resolution has gone up, which means we're now dealing with 1.12 µm pixels rather than 1.3 µm pixels on the OnePlus 2's OV13860. At a quick glance one would expect that this means image quality will certainly be worse, but improvements in sensor technology from year to year make smaller pixel sizes more viable, and one can't conclude anything just based on the sensor specs alone.

The lens system remains similar between the two phones, with the same aperture and a similar focal length. OnePlus has also changed from laser autofocus to PDAF. While this is an upgrade in many respects, PDAF generally does not work well in low light while laser autofocus does, and so it's not the case that the move to PDAF will improve autofocus speeds in every situation. That being said, the OnePlus 2 is notoriously bad at focusing in the dark even with its laser AF so the actual focus itself in the dark may be improved with the OnePlus 3 even if it's not as fast.

Still Image Testing

This first daytime test involves a scene with variant lighting conditions, which can cause some smartphones to overexpose their photos. There's also a lack of direct sunlight throughout the entire area due to the leaves of trees, which provides a good way to see how different phones handle the balance of exposure, noise processing, and sharpening to maintain detail in both bright and dark areas.

The OnePlus 3 performs very well in this test. Compared to a device like the iPhone SE or iPhone 6s there's definitely a greater level of detail and sharpness in the more distant objects, and in the branches and leaves of the tree. The OnePlus 3 also has a more natural exposure than the iPhone, but the white point does skew toward green which gives the entire photo a green look to it. The OnePlus 2 doesn't suffer from this issue, but it ends up overexposing the photo which produces a less natural looking appearance overall. One interesting point is that the OnePlus 3 has removed more detail in the grassy area than the OnePlus 2, which is a regression in detail that I didn't expect to see. My only other complaint is that the OnePlus 3's photo does push a bit too hard with the color saturation, and the Nexus 5X provides a photo that is closest to what the scene actually looked like to my eyes.

For a $400 smartphone the OnePlus 3 does very well here. OnePlus just needs to do a bit of tweaking to their image processing, but they're in a much better place than they were with the OnePlus 2 when it originally launched. Nothing here stands out as a problem with the camera itself, and OnePlus has been known to make many changes to image processing with their updates to OxygenOS so I expect that there will be continued improvements to still image quality as time goes on.

This next scene is a fairly standard outdoor scene, and the only area of difficulty would be capturing the detail in the distant bushes without producing significant sharpening artifacts. In this scene the OnePlus 3 again performs quite well, and I would actually say that it provided the best photo of the devices that I tested. Compared to the OnePlus 2 there's a noticeable improvement in sharpness, which is visible by looking at the brick texture of the building on the left and the leaves of the tree on the right. The colors in the scene are also more true to how it actually looked at the time. The one thing that doesn't look quite right are the bushes in the distance, which end up looking flat. Most of the other devices end up avoiding this, but they also suffer from areas that are overexposed and over sharpened, so every device has a trade-off here.

Ultimately there's not really anything that OnePlus is doing wrong here. The exposure and white balance are correct, and the level of detail is high, with significant improvements over the OnePlus 2's sharpness across the frame, and especially near the edges.

The low light performance of the OnePlus 3 improves significantly over the OnePlus 2. As I mentioned at the start of the page, the OnePlus 2 has serious issues with achieving focus in low light, and the shots here that I used for it are the best of many attempts. The OnePlus 3 is able to focus, and on top of that the detail retained in the image and the exposure are both very impressive. Of the devices I've compared I would say that the OnePlus 3's image is actually the best one, with the iPhone 6s coming after but being worse due to the increased noise level and lesser detail retained. I'm no longer testing the Nexus 5X using its HDR+ mode because Google has had more than enough time to fix their issues with normal image processing by now, and when you compare the OnePlus 3 to the 5X's stock processing it's clear that the OnePlus 3's low light capabilities are superior.

While the previous test was a low light test with lamps illuminating the area, this next test is really just to see how far each camera can push its exposure and how much detail can be maintained while also doing proper chroma and luma noise reduction. In this case it's again clear that the OnePlus 3 leads the other devices, with the OnePlus 2 failing to focus properly again, and every other device being decidedly worse with the detail retained, overall exposure, and noise across the frame.

In all my test cases the OnePlus 3 improves significantly over the OnePlus 2. OnePlus has come a long way from the early days of the OnePlus One where even basic noise processing didn't seem to be implemented properly. I think the OnePlus 3 provides great image quality for a $400 device, and it addresses pretty much every issue I highlighted with the OnePlus 2, which shows that OnePlus is listening to reviewer and user feedback to improve their devices year over year.

Video Recording

The OnePlus 3 certainly improves over its predecessor with still photos, but it's not clear whether the same can be said for video recording. Looking at the files doesn't show any improvement in quality from an encoding perspective, as OnePlus is still encoding UHD video at 42Mbps with the H.264 baseline profile. The audio is kept as a dual channel 96Kbps AAC track as well. OnePlus still has room to improve with the basic image processing and the stabilization provided by the OIS even if the video doesn't improve in bitrate, and I've recorded two videos to demonstrate the video quality when moving as well as from a mostly stationary perspective. Like many Android devices, the OnePlus 3 can only record UHD video for up to ten minutes.

Unfortunately, the UHD video recording on the OnePlus 3 isn’t very impressive. There are a number of issues with the footage, starting with stability. OnePlus is making use of their OIS, but they’re doing so in the same flawed manner as every other Android manufacturer who has implemented OIS when recording video. The problem is that the OIS is used to keep the video as stable as possible, which then fails when the OIS reaches its travel limit and resets, causing an extremely rapid shift in camera position which shows up as jerky motion in the video. This doesn’t pose a problem if you just point the camera somewhere and start recording, but if you plan to move at all while recording it makes for some really jarring footage.

In addition to jerky footage caused by the stabilization implementation, I’m noticing some severe issues with macroblocking that makes the footage look much lower in quality than you would expect from a UHD video on a modern smartphone. In both video samples you can see it in the sky and on the concrete paths, and it results in footage that just isn’t competitive with something like the iPhone SE which also costs $399. These artifacts aren't a result of any image compression on Youtube either, as they exist in the source files as well.

The OnePlus 3 improved significantly with still image quality, but the video quality has some serious issues. Most vendors are pushing higher bitrates than OnePlus is, and Apple is still ahead of all the other smartphone vendors here. It's not as though the OnePlus 3's video quality is terrible, but I feel as though there was room for improvement here but no action was taken.

Battery Life

The OnePlus 2 had many problems, but something you could generally count on was that it provided good battery life. Unfortunately, the caveat was that the phone usually ran on four Cortex A53 cores so it performed only a bit better at CPU tasks than a $100 Moto E LTE, but that's another story. With the OnePlus 3 you no longer have to deal with exceptionally poor performance, and with the battery being made smaller at the same time as OnePlus moves from an LCD to an AMOLED display it's difficult to say what happens to battery life in the process. To evaluate the OnePlus 3's battery life under various scenarios I've run our 2016 WiFi web browsing battery test, PCMark's battery test, and GFXBench's Manhattan 3.1 battery test.

The OnePlus 3 regresses slightly from the OnePlus 2 in our web browsing battery test. However, it's also worth noting that the OnePlus 2 had crippled web performance by only enabling the SoC's A53 cores, and with the OnePlus 3 being over twice as fast with JavaScript performance it's worth the tiny hit to battery life. Looking at the broader market you can see that the OnePlus lasts slightly longer than the Nexus 6P, but trails the Galaxy Note5 by about the same amount.

In my own usage I haven't noticed any problems with web battery life on the OnePlus 3. OnePlus definitely could have put in a larger battery, but it would have made the phone thicker and heavier which would have a negative impact on its ergonomics and usability. The OnePlus 2 basically feels like a brick in the hand, and all you get for it is an extra 300mAh over the OnePlus 3. The OnePlus 3 much nicer to hold in the hand, and the idea that you should compromise that by making it 3mm thicker and 30g heavier just to boost the battery capacity by 10-15% is ridiculous.

For those who are interested, I measured 6.47 hours when running this test over LTE. I've decided not to compare this result directly to our past reviews because I'm still unable to achieve a strong enough signal over LTE to get results that are comparable to those run by Josh and Matt, but the drop in battery life when running over LTE was only about thirty minutes which is a great result for -97dBm on LTE.

In PCMark's battery test the OnePlus 3 continues to do quite well. As I showed in the performance section, the OnePlus 3 improved over the OnePlus 2 a great deal in PCMark's tests, and yet it also lasts longer in a battery benchmark running those same tests. PCMark's battery test is a good indicator of what battery life you can expect when performing a variety of different tasks that stress different parts of the system, and the fact that the OnePlus 3 only loses to the larger Galaxy Note5 and Huawei Mate 8 speaks very well of its battery life.

The OnePlus 3 does exceptionally well in our GFXBench Manhattan battery test. While it's by no means a leader in terms of absolute battery life, the performance it achieves is impressive to say the least. It's important to note that this is an on screen test, and so while the OnePlus 3 is a bit behind the iPhone 6s for sustained performance, it's also pushing a much higher resolution. The fact that the phone maintains its frame rate for over two hours is also an improvement over pretty much every other Android device, with the LG G5 coming close but exhibiting small oscillations that the OnePlus 3 doesn't have. Suffice to say, the OnePlus 3 provides a substantial improvement over the OnePlus 2 here, and I think anyone would agree that it's more fun to play a game at 30fps for two hours than to play it at 7fps for three.

In the end, the OnePlus 3 generally does as well or better than its predecessor in our battery life tests when you consider their context. In our 2016 web test battery life has dropped a bit, but it's not a significant decrease even though performance has improved immensely. PCMark battery life improves, and that's a test that reflects real world usage quite well. In GFXBench it doesn't last as long, but sustained performance is three times as high, and the frame rate the phone can maintain is high enough that a game with the visual fidelity of the Manhattan benchmark would actually be playable at 1080p on the OnePlus 3.

Charge Time

One of the biggest controversies regarding the OnePlus 2 was the lack of support for quick charging. OnePlus actually included a 10W charger so it wasn't as though you were limited to 5W speeds, but nonetheless you weren't able to take advantage of chargers that supported Qualcomm's Quick Charge protocol. The OnePlus 2 and the OnePlus 3 both use USB Type-C connectors, but there's no support for USB Power Delivery. With the OnePlus 3 there's now support for quick charging, but in an unconventional way.

The OnePlus 3 introduces a new standard for quick charging that was created by OnePlus, which they call Dash Charge. According to OnePlus, Dash Charge moves much of the power management processes to the charger itself rather than the phone, which reduces the heat generated by a device as it charges. There isn't much technical information about what exactly is going on, but a reasonable guess is that the DC/DC voltage conversion is now going on at the charger instead of the device, which means the phone only has to handle the current limiting. Dash Charge also operates at 5 volts, and the included charger is a 5V 4A block for 20W of output power. It's worth noting that the USB Power Delivery implementations that we've seen operating at 15W also use 5 volts, so this isn't necessarily something unique to Dash Charge.

Of course, there is a caveat with OnePlus making their own protocol is that you're limited to their charging blocks.  On top of that, you're limited to using OnePlus's cords, with the charger not providing quick charging using other USB Type-C cables such as the Google-branded ones that I have. This is a significant drawback compared to Qualcomm Quick Charge and USB Power Delivery, although I would imagine most users will use the included charger and cable so it may not pose much of a problem in practice.

As a OnePlus-specific charging implementation, Dash Charge may not be as convenient as USB Power Delivery or Qualcomm Quick Charge, but it certainly charges the phone quickly. At 1.44 hours to go from 0 to 100% there's not really anything to complain about with the actual time to charge. 

While Dash Charge is interesting in how it charges quickly and actually does manage to keep the phone cool while doing so, I'm not really sure if it's worth the trade-offs. If you lose your OnePlus cable you have to buy a new one from OnePlus, and you can't quick charge with the large number of Qualcomm Quick Charge accessories available on the market. If nothing else, Quick Charging is here on a OnePlus device, but it has more restrictions than one might have hoped, and it's not clear if the benefits are worth it.

Final Words

Update: With OnePlus's addition of an sRGB mode my verdict on the phone has changed. Click here to read my more recent conclusions, which complement those in this section.

As I think about the OnePlus 3 and all of its aspects, I'm left with both some good and bad surprises, but mostly good ones. When I reviewed the OnePlus 2 I didn't really understand how OnePlus could regress from the OnePlus One in so many ways. Part of it was probably due to the end of the partnership with the Cyanogen team, which seemed to have input on matters such as the display calibration. Another part was due to the state of Qualcomm's SoCs at the time, and OnePlus's less than optimal choices for managing the thermals in circumstances like web browsing. Beyond all of that, I'm reminded of a statement that a friend and colleague of mine made regarding the OnePlus 2 the day my review went live. What he essentially said was that it's no longer sufficient to do minimal engineering and just sell a phone on the basis of a low price and good specs on paper. I think there's a lot of truth to that, and I think moving beyond that kind of design process is something that OnePlus succeeded in with the OnePlus 3. Before I come to a conclusion on the phone, I'd like to go over its core aspects and how they measure up in this increasing competitive market.

The design of the OnePlus 3 really is a level above that of the OnePlus 2. The move to an aluminum unibody combined with reduced thickness and mass makes the device feel of a might higher quality than the OnePlus 2, and it sits more comfortably in the hand. The entire design also feels much more thought out. When you look at the OnePlus 2 the little island with the camera, flash, and IR module looks like it was just slapped on without any thought, while on the OnePlus 3 the camera is met by the antenna bands and has the LED flash set right underneath it. There's just a greater cohesiveness to the entire device, and really my only complaint comes back to the slightly misaligned 3.5mm jack, but that's quite a nitpick. If you were a fan of the OnePlus 2's sandstone back, you can get a case for the OnePlus 3 made of the same material, which addresses that section of the OnePlus fanbase.

While Snapdragon 810's throttling issues certainly presented problems, the OnePlus 2 made the situation even worse with its ridiculous throttling mechanism for Google Chrome that would shut off the A57 cores instantly. This provided web performance that was in the same range as the Moto E and the Moto G, which were available for only $100-200 at the time. Even outside of Chrome, performance in CPU-bound tasks was often worse than the OnePlus One. This could be felt in apps, and throughout the entire UI which made the phone feel painfully slow and sluggish. The OnePlus 3 addresses all of these problems, and it provides class-leading performance among Android devices at this price, while also being one of the fastest devices among all smartphones.

The OnePlus 3 takes some great photos. Whether you're shooting in the day or at night, the sharpness and detail retention is quite good. Like all manufacturers, OnePlus still has some room for improvement. My first photo test exposed a case where a scene with a great deal of foliage could skew the white balance toward green when it shouldn't, but these kinds of issues can be improved over time. Images taken in the dark also demonstrate a good balance between noise reduction, sharpening, and exposure, and of the devices I tested they were clearly the best. Video quality isn't at the same level, and despite the relatively high bitrate there are very visible macroblock artifacts when moving the camera, and the OIS stabilization just doesn't work very well.

Unfortunately, the display really kills the phone for me. Based on every other aspect I think it would be a no-brainer to replace the Nexus 5X with the OnePlus 3 as my daily driver, even if it is bigger than I'd like. I simply can't though, because I just feel unpleasant whenever I look at the OnePlus 3's display. I don't think it's a stretch to say it's the worst display I've examined during my time at AnandTech, as despite the Nexus 6's faults it didn't have the ghastly blue appearance of the OnePlus 3.

Of course, many people may not care about the display accuracy to the extent that I do. If you're part of that group then I think the OnePlus 3 should be high up on your list of phones to consider, because beyond the display, and to an extent, the camera, the OnePlus 3 is a great smartphone. For someone like me the inaccuracy is just far too severe to be tolerable. I've used many smartphones where the display calibration is anything but perfect, like the Moto E, the Honor 5X, and the Zenfone 2, and they were usable because the extent of the errors wasn't that severe even if the display wasn't something you'd want to edit professional photos on. The OnePlus 3 just pushes things way too far, and at least in my opinion the decisions made regarding the display's color characteristics demonstrates that OnePlus needs to bring people into the company who really understand the complexities regarding displays and color management.

What gives me hope is the quick response from OnePlus on the issue. While it's concerning that OnePlus didn't understand that an sRGB mode is needed and that NTSC is completely irrelevant, their quick response and plans to implement an sRGB mode show great initiative and how a smaller company is able to react quicker to these situations than a large company can. It remains unclear as to when an update with an sRGB setting will come, and I'm skeptical about how much the display can be fixed after shipping as the unconstrained gamut is hardly the only issue, but there's still hope that things can be improved. I will definitely be revisiting the OnePlus 3 when this update ships, and I hope that my conditional recommendation can become an unconditional one. 

As it stands, my recommendation on the OnePlus 3 is exactly that, a conditional one. If the problems with the display don't bother you then there's a lot to like here. Despite the small problems it has besides the screen, the OnePlus 3 represents a really great device at a more than fair price. If OnePlus can actually fix the display with an OTA update it will be the obvious recommendation for an Android phone at $400.

Right now my best advice to potential buyers is to think about whether or not the inaccurate display colors will bother you. If it won't, and if you're looking for an Android phone priced at around $400, then the OnePlus 3 should be on your list of considerations, if not at the top. It's obviously important to also consider whether or not you can comfortably use a 5.5" smartphone, but I assume that by this point smartphone buyers have figured out what sort of device size they enjoy using. I can't yet replace the Nexus 5X as my daily Android phone, but I hope that I'll be able to soon after OnePlus resolves this problem. I'll be keeping my eye out for updates to OxygenOS, and I hope you'll keep an eye out for my second look at the OnePlus 3's display, which I hope I'll be able to do soon.