Xiaomi’s worldwide launch has been heralded for years, and with the Xiaomi Mi Note 2 it looks like the final pieces are falling into place. As Xiaomi’s first flagship phone to offer a model with worldwide frequency band support, the Mi Note 2 offers an exciting look into what we can expect from Xiaomi as they continue to expand internationally.

In this review, we’ll take an in-depth dive into the Xiaomi Mi Note 2. Rather than listing specs and talking about how the experience felt, this feature attempts to provide a thorough look with contents relevant to our reader base. At XDA, our reviews are not meant to tell a user whether a phone is worth buying or not — instead, we try to lend you the phone through our words and help you come to the decision by yourself. Before getting started, let’s get the specification sheet out of the way:

Device Name

Xiaomi Mi Note 2

Release Date/Price

Available Now, Starts at CNY 2,799 (USD 400)

Android Version

6.0.12017-05-018.5.3.0

Display

5.7 inch 1080p P-OLED (386 ppi)

Chipset

Qualcomm Snapdragon 821 MSM8996 Pro-AC: Quad Core, 2×2.34 GHz Kryo + 2×2.19 GHz Kryo, Adreno 530 GPU

Battery

4070 mAh, Quick Charge 3.0

RAM

4GB | 6GB LPDDR4 1866 MHz

Sensors

Fingerprint, Accelerometer, Gyroscope, Proximity, Compass, Barometer

Storage

64GB | 128GB UFS 2.0

Connectivity

USB 2.0 Type-C, 3.5mm audio jack, Dual-SIM slot (nanoSIM), IR Blaster

Dimensions

156.2 × 77.3 × 7.6 mm (74.2% screen-to-body)

Rear Camera

22.5 MP Sony IMX318 sensor, 6.9 mm sensor (Type 1/2.6), 1 μm pixels, EIS, PDAF, ƒ/2.0, 4k 24 Hz Video, 720p 120 Hz Slow Motion

Weight

166 g

Front Camera

8 MP Sony IMX268 sensor, 4.9 mm sensor (Type 1/3.61), 1.12 μm pixels, ƒ/2.0, Auto Focus

Index

 DesignSoftware - UISoftware - UXPerformanceReal World UXCameraDisplayBattery LifeAudioDeveloper RelationsFinal Thoughts


Design

Design is always one of the hardest things to describe about a phone, and that especially holds true for devices that will often be ordered without seeing them in person. To give someone an idea about what the tactile feel of a device is from across the internet requires comparisons to other popular devices to create an understanding of what the device looks and feels like. Thankfully, in the case of the Xiaomi Mi Note 2, there is a device that feels almost identical in the hand that you can probably find in your local cell phone stores.

While the curved front and back appears to be an almost eerily close match with the Samsung Galaxy S7 Edge, the feel in hand reminds me more of the slightly older Samsung Galaxy S6 Edge+ (Samsung’s 5.7” device with a curved screen from the year before).

The curved back definitely helps with gripability, however it just doesn’t feel quite as pronounced as the curve on the S7 and S7 Edge, which makes a noticeable difference. The S7’s back curves in much further, allowing it to rest in your hand more easily, in turn helping you wrap more of your hand around the phone for a tighter grip.

The volume rocker and power button are positioned on the right side of the device, and are a bit further up the device than we have come to prefer. They are just high enough to require most people to reposition their hand in order to press the volume keys if holding the device in their right hand, and to require complete repositioning to hit any buttons with your left hand. Thankfully, the device can be woken with both Double Tap To Wake (DT2W) and by pressing the home button (which houses the fingerprint sensor).

The buttons generally feel solid, with firm tactile feedback and a soft audible click. On our testing device, the home button can sometimes get stuck if you press on the left side of it, however so far unsticking it has been as simple as pressing down on the button again. This isn’t something wholly exclusive to the Xiaomi Mi Note 2, as other devices with home buttons can get “stuck” in a similar fashion. While it is not really a cause for concern, it does happen more frequently on our device than we would like to see.

The SIM card tray can be found opposite the volume rocker, and would be almost unnoticeable if not for the SIM ejector hole, as it sits flush with the frame. The top of the device houses the 3.5 mm jack (which is missing on the Xiaomi Mi 6), a microphone, and the IR blaster, while the bottom houses another microphone, the speaker, and the USB Type-C 2.0 port.

 

Despite having two equally-sized speaker grilles on the bottom of the phone, only one of them houses a speaker, with the other one (which houses the microphone) being the shape that it is primarily for design reasons (a very popular practice nowadays). This ends up not being an issue however, as the Xiaomi Mi Note 2 still can be quite loud at times. The noises for locking and unlocking the phone in particular are ridiculously loud in their default configuration, however the speakers do run into some issues with audio clarity when playing music, which we talk about a bit more in the audio section below.


Software – UI

We’ve written extensively about how MIUI differs from AOSP in previous reviews (such as the Xiaomi Redmi Note 4 and the Xiaomi Redmi 4), from the iOS-like homescreen to the differences in the notification shade, so for this section we will be focusing heavily on device specific performance.

While the Xiaomi Mi Note 2 officially supports English (one of just five languages offered on the Chinese ROM), there are still substantial portions of the UI that have not been translated on the build we are using. The resulting UX leaves you with a tantalizing glimpse of what the phone could be (and possibly what it is under other language settings), but which simply isn't at the level expected from flagship phones.

It doesn’t stop on the device itself however. The english language page for the Xiaomi Mi Note 2 on Xiaomi’s website has numerous spelling and grammar errors, the majority of which could be caught with a single read through by a native speaker. It really is a wonder that Xiaomi doesn’t hire someone to go over their global website at the very least, if not the device as well. They could quite literally spend a couple bucks on a freelancer website to get someone to quickly proofread their product page, and they would end up creating a substantially more user friendly and polished experience (although ideally they would want to work with someone consistently who is familiar with the technology).

As this is Xiaomi’s first phone with “Global LTE band” support, it thankfully has received a Global ROM as well, which ideally brings better support for other languages and support for more languages, in addition to other changes like having a different set of preinstalled apps. If Xiaomi still intends to enter the North American market, they will need to have a seamless experience in the local languages (including English, French, Spanish, and many others). Small irritations can quickly build up to create a negative experience, and untranslated popup boxes where you can’t tell what either option is are more than just a small issue.

Substantial portions of the settings menu on our device have not been translated either, including the settings for the stock lockscreen. By default, the lockscreen cycles through different sets of pictures, which are curated by Xiaomi. You can select which sets you are interested in, however as they have not been translated to English, you are left with just an abstract picture and the translation software of your choice to try to guess what each category is for.

The hyperlocalization of the device continues on into the built in browser, which ships with a couple options that you can choose between for the search engine in the omnibar, all of which are Chinese language websites. Unfortunately, it does not appear to be possible to set a custom option for the omnibar, leaving you with a lackluster search experience in other languages.


Software – Features & UX

I've mentioned previously how I can be quite picky about how Halo-style navigation features are implemented, and Xiaomi seems to have hit the mark. Quick ball is a proper implementation of floating controls. It opens up quickly, and lets you access what you wanted and get back to what you were doing. It is smooth, it is fluid, and it is fast.

One kind of nice feature is that the phone wakes up from being powered off to play alarms, which is both good and bad. It’s good in that you won't miss your alarm if you do something like shutting the phone off overnight to save power, but it can potentially cause problems if you meant for it to stay off and forgot about the alarm (for example, if you meant to turn it off long term, or if you turned it off to avoid all noises while you are in a meeting, or if are in a room where you are not allowed to have your phone on). Of course, being keenly aware of this behavior goes a long way and can minimize or neutralize any issues you might otherwise encounter.

As we mentioned above in the UI section, Lockscreen pictures often have descriptions, but they are all in Chinese. There is not even an automatic translation into the language of your choice, despite Xiaomi partnering with Microsoft, who are heavily pushing Bing Translate’s abilities, and holding it up as an alternative to Google Translate. Microsoft clearly thinks that their translation capabilities are ready for prime time, having partnered with Facebook to bring automatic translation to Facebook posts, so it is interesting to see the lack of it here. It’s not clear if this was a conscious decision to leave it out due to the possibility of errors, or if it was simply a case of not realising that it was a possibility.

Lockscreen pictures are questionable at times. By default, some of the lockscreen images appear to relate to ongoing news stories, and can occasionally have some not safe for work images attached. For example, when the Victoria Secret fashion show was happening, our device cycled to some pictures which probably shouldn’t have been enabled by default. The images were fine if you’re expecting them, but being surprised by someone wearing just their underwear at the wrong time can be… frustrating, and can result in awkward explanations.

Along the same lines, many of default the lockscreen images that the phone cycles to are of Chinese models posing in magazine-style images, which stands in stark contrast to how many other similar services such as Windows Spotlight and Chromecast Backdrop are avoiding having any individual person as their main focus, and instead prioritizing beautiful landscape or urban photography and macro images.

Pictures appear to be chosen without any regard to how they will interact with the text on the lockscreen, which can unfortunately cause some readability issues at times. That being said, for the sake of fairness, only Microsoft seems to be doing that properly, and even then, primarily for Bing search, not their Windows Spotlight.

One particularly annoying thing that the phone does is that the display keeps flashing on seemingly without reason if you leave it sitting for a bit. It appears that it may flash on when the lockscreen image changes, although we are not sure at this point in time.

Many of the built-in apps require authentication in order to use, which Xiaomi has chosen to do by having the phone send an international text to their servers to verify the number. This is quite strange, as most SMS based device authentication systems instead have the system send a text to the phone, specifically to avoid problems with international texting and devices that can't send texts (such as landlines and data-only lines). The authentication is pervasive throughout the phone, with many apps requiring it that probably shouldn't.

One that jumps to mind is the built in Virtual SIM card app, which requires you to verify a separate SIM card via SMS in order to use it. The Virtual SIM card app is designed to allow you to buy cellular connectivity packages directly from your phone, in preparation for ESIM (which will allow phones to join the cellular network of your choice through software, instead of physically inserting a SIM card, which in turn will reduce the number of openings on the phone and allow OEMs to waterproof phones more thoroughly). Unfortunately the Virtual SIM card app is entirely in Chinese, despite the international focus of the app. It is understandable that it is meant primarily for people temporarily traveling internationally from China, but it would have been nice to see it formated in a way to be usable for international customers as well.

Xiaomi has included some nice features that help with navigation on the Xiaomi Mi Note 2, like the ability to swap the back and recents buttons to fit the order that you prefer, as well as the ability to switch to having them mapped to swipes of the fingerprint sensor. The swiping method was surprisingly useful, helping prevent accidental button presses and making both back and recents easy to reach.

The fingerprint sensor is extremely quick to authenticate and is remarkably accurate. It is easily one of the best fingerprint sensors that I have used to date. While it would be nice to see further development of fingerprint sensors in multi-factor authentication for Android (as a fingerprint is a username, not a password), the speed and accuracy make it convenient to use, which is critical for a convenience feature, and something that not all fingerprint sensor implementations have caught up with yet.

Performance

The Xiaomi Mi Note 2 is not going to be breaking records for a Snapdragon 821 device, but it doesn’t perform poorly either. It performs just as it is expected to, and that is fine to see from a device running on a popular platform like the Qualcomm Snapdragon 821.


CPU & System

The Qualcomm Snapdragon 821 inside of the Xiaomi Mi Note 2 behaves exactly how a Qualcomm Snapdragon 821 is supposed to behave, and that is fantastic. It has great performance across the board, which can result in fantastic results when combined with a software stack that isn't overly bloated. The Xiaomi Mi Note 2 also saw very low variance in our testing, which helps deliver a consistent user experience.

This shows up in both Geekbench 4 and PCMark 2.0, where the Xiaomi Mi Note 2 keeps up with the rest of the pack when it comes to flagship devices. The Xiaomi Mi Note 2 does particularly well in the PCMark 2.0 Photo editing test, where it pulls well ahead of the Pixel XL, OnePlus 3, and LG V20, but falls behind the latter two in the PCMark 2.0 writing test.

Sustained performance is quite good as well. In our Geekbench 4 throttling test, the performance drop from the first run to the lowest run is less than 7% in multi core, and less than 3% in single core performance. The Xiaomi Mi Note 2 got a bit hot over the processor in the top corner, however at the midframe and by the base of the phone, temperatures drop to a reasonable level.


GPU & Gaming

Just like with the CPU, GPU performance on the Xiaomi Mi Note 2 is quite good. The phone performs right where it should with the Qualcomm Snapdragon 821's Adreno 530 GPU, and it provides a reasonable gaming experience as a result.

In both 3DMark and GFXBench the Xiaomi Mi Note 2 stays right with the rest of the pack. While performance is quite good, it falls well behind the Google Pixel XL in terms of variance, resulting in a less consistent experience.

In our sustained performance testing, the Xiaomi Mi Note 2 gets up to its maximum heat very quickly, and throttles accordingly. In our 3DMark test, one run is enough to get within reach of the maximum temperature, resulting in a score drop of 25%, but it levels out quickly after that, leaving you with acceptable sustained performance.

Testing sustained performance with GFXBench shows similar results, with one large drop after the first run, before it mostly levels off for the rest of the test.

Memory & Storage

Having 64GB of storage standard and 128GB in the high end model is a fantastic feeling. With 56 GB of free space by default on the 64GB model, there is substantial room to take pictures, install apps, and take media with you. While SD cards are very useful, there are still some things that you can only really do with internal storage, so it is always nice to see a device with space to spare.

Speaking of SD cards, it still is a bit disappointing that Xiaomi currently seems to be avoiding using SD cards in their flagship Mi series phones, while widely implementing them in their entry level Redmi series phones. There is something about being able to just throw a 200GB SD card into the device to carry all of your pictures/music/movies/videos/etc. with you that is a bit freeing. With the recent focuses on caching videos from Netflix and Youtube, local storage is becoming increasingly important yet again.

Xiaomi Mi Note 2

Sequential

Random

Read Speed

268.16 MB/s

14.82 MB/s

Write Speed

55.34 MB/s

3.47 MB/s

App Loading Time Test (in milliseconds)

The Xiaomi Mi Note 2 gets fantastic storage performance thanks to its UFS 2.0 flash memory. With Androbench set to 1 thread and a 256 kB sequential buffer, we see good performance in both read and write speeds, which go a long way towards creating a smooth experience.

That performance shows up in app loading times, where the Xiaomi Mi Note 2 goes toe to toe with flagship phones such as the OnePlus 3T and the HTC 10.

Real World Performance

The Xiaomi Mi Note 2 unfortunately can get quite hot, even in regular use. It doesn't reach scorching hot levels such as the ones we saw with the Ulefone Metal, but it still is more than you would expect from a Snapdragon 821 device. This is in part due to the substantial power draw brought about by the two highest power states on the faster clocked version of the Snapdragon 821, but it ultimately is up to the clock speed scaling and thermal throttling profiles that Xiaomi has decided to use.

Xiaomi Mi Note 2 Frame Time Screenshot

The processor comes with a couple tricks up its sleeve that help with UI fluidity, including maximizing clock speeds while opening any app (not to be confused with maximizing it when using specific apps), which can help prevent issues like frame drops during those relatively processing intensive moments -- in simple terms, this helps ensure the processor can’t bottleneck launch times.

Using the Xiaomi Mi Note 2 is incredibly smooth. There are minimal frame drops, and every interaction with the device from switching home screens to scrolling through the menus feels fluid. While this should be how devices are expected to operate at this point, some manufacturers still run into issues optimizing their software.

That being said, there still are some small quirks with UI fluidity on the Xiaomi Mi Note 2 which can be irritating. For example, when shutting off the phone, the button that appears on screen after holding the power button requires two taps, and has a small position shift between the first and second tap that can make it easy to accidentally miss if you’re moving too quickly.

A few responsiveness issues aside, the Xiaomi Mi Note 2 generally presents a pleasing experience to interact with, with smooth animations and minimal frame drops.


Camera

The Exmor RS IMX318 image sensor is a bit of a new favourite for companies looking to advertise high resolutions, with it being used in the Asus Zenfone 3 Deluxe/Ultra and the ZTE Nubia Z11 mini S, as well as in the Xiaomi Mi Note 2. That list will likely continue to grow in the future, as Sony views the IMX318 as the direct successor to the popular IMX230 that appeared in devices like the Moto X Style/Play/Force, the Honor 7, and the Sony Xperia XA Ultra.

With a 6.858 mm (Type 1/2.6) sensor and an active resolution of 5488×4112, the IMX318 has 1μm pixels, which are absolutely tiny. While these small pixels make the high resolution possible, they also reduce the amount of light captured per pixel, and can dramatically harm low light performance.

The IMX318 uses a hybrid autofocus solution that takes advantage of both PDAF and contrast-based autofocus, which Sony brags is capable of focusing in just 0.03 seconds on an overcast day. Despite that, the Xiaomi Mi Note 2 is often slow to focus, which comes as a bit of a shock. The device appears to lean quite heavily on its contrast based autofocus, even in low light.

The Xiaomi Mi Note 2 is ridiculously slow when taking HDR photos,especially in low light. Surprisingly, it is not processing the image that takes a long time for this device (despite it being a common problem on other phones). If anything, the Xiaomi Mi Note 2 processes HDR photos extremely quickly. It is the actual act of capturing the photo itself that is slow. From when you hit the capture button until when the screen unfreezes can take a couple seconds, and if you move the phone at all during that time frame, the entire picture will come out blurry.

In daylight the Xiaomi Mi Note 2 has bright punchy colours that have a tendency to oversaturate and underexpose, resulting in a loss of detail in the shadows. The high resolution camera performs quite well in daylight, bringing out fine details that are missed by both the HTC 10 and the OnePlus 3T, like the slight indent around the letters on the Green P sign.

While the Xiaomi Mi Note 2 performs admirably in daylight, that performance starts to fall off as the sun begins to set. In twilight the rear camera still can produce a nice (if oversaturated) image, however the images start to appear a bit flat in areas, as shadow detail drops off. It is most noticeable in the evergreen trees in the background of the image below, with the branches blending together into one dark blob. Outside of those pain points however, the image is still more than acceptable.

The camera automatically activates Handheld Twilight mode (HHT) in low light situations. HHT works by raising the ISO in order to allow for a shorter exposure (to avoid issues with handshake that often come into play in low light photography). That alone would result in substantially more image noise, so Xiaomi then stacks 6 subsequent images in an almost HDR-esque fashion in order to cancel out the noise introduced by the higher ISO setting. In theory this method should work quite well to improve the image quality for stationary objects, however moving objects will be captured with more image noise than they otherwise would have, as they will be based on a single frame instead of using the full stack of 6.

While the high resolution sensor certainly helps with detail capture in daylight, the tiny pixels have relatively poor light sensitivity, and result in a lot of noise, a lack of detail, and blurry images in nighttime scenes. This is especially noticeable in the cropped image of the tree at night, where the substantial noise on the Xiaomi Mi Note 2's image almost makes it look like you are looking at the image through water.

The Quick Shot camera is another interesting feature, although it has some bugs. It allows you to take pictures without even needing to turn on the screen, just by holding the volume down button (this seems to be a popular feature in Chinese devices). Unfortunately it appears to default to an exposure time of just 1/62 of a second and an ISO of 400 for the first photo in every series. This results in exceptionally dark photos in anything other than broad daylight, which simply is a shame. It was likely done to decrease the amount of time until the first photo is captured, but most of the time that first photo ends up just being a waste of space and time as a result.

The photos after the first one will have their exposure time and ISO set depending on the scene, resulting in much higher quality images. Even then, it still trends towards shorter exposure lengths and higher ISO than a regularly taken picture would have. As well, in a considerable number of my testing photos, the camera was out of focus, as it seems to take the Quick Shot photos right away when the camera is ready to capture (approximately 1 every 0.466 seconds), rather than waiting for the camera to be focused. Those two issues combined so that in our testing, you would often have to wait for the third or fourth Quick Shot picture before something usable was captured (and it occasionally would not be able to focus at all in poor lighting conditions).

Overall, the Xiaomi Mi Note 2 takes fantastic pictures (especially in daylight), but they simply don’t hold up to the level of other flagship phones like the HTC 10 and Samsung Galaxy S7.

The front camera is also quite interesting. It uses the Sony Exmor RS IMX268 image sensor that was recently found in the wide angle camera on the LG G5, and which Sony views as a partial successor to their Exmor R IMX219 sensor (as found in the LG V20, the Sony Xperia XA, and the Nexus 9). This is a bit of a lower end image sensor compared to the rear camera (albeit still relatively high end for a front facing camera), with contrast based autofocus, an active resolution of 3872×2192 (although the Xiaomi captures at 3840×2160), and a sensor size of 4.868 mm (Type 1/3.61) with 1.12μm pixels. Xiaomi paired this potent combination with an ƒ/2.0 lens, which in theory should provide excellent low light performance.

While the colours on the front camera of the Xiaomi Mi Note 2 are pleasing and it does a relatively good job of detail preservation when the autofocus manages to get a lock, the dynamic range is a bit limited, the colours lack warmth, and the beautify modes (which are enabled by default) can push things a bit too far towards the uncanny valley.

As with the rear camera, this competitiveness falls apart in low-light scenarios, where the Xiaomi Mi Note 2's small pixels result in substantial amounts of noise, and poor light gathering abilities.

It is important to note that having autofocus on a front facing camera is a relatively new feature (with only a couple phones like the HTC 10 and the Sony Xperia M5 having it) which creates an often surprisingly different shooting experience. While autofocus does bring improved image clarity when compared to a fixed focus camera, it comes with two major downsides which have historically driven OEMs away from implementing it. The first is that it costs more and takes up more internal space than an equivalent fixed focus camera, which can have substantial effects on the design process.

The second is that unlike with a fixed focus camera, you cannot immediately start shooting when you open the camera, you have to wait for the camera to focus. This may not seem like a big deal at first glance (especially with autofocus being nearly universal for rear cameras), however the shorter focusing distances and quick shooting scenarios that front cameras often face can create an extremely challenging environment for even the best autofocus systems to operate in.

Unfortunately, the Xiaomi Mi Note 2’s front facing camera does not have the best autofocus. It uses a contrast based autofocus system that can often take a second or two to focus. When combined with how it captures right when you hit the shutter button instead of forcing you to wait for it to focus like most rear cameras, it resulted in numerous out of focus shots in my testing.

That is not to say that it is a bad camera. The Xiaomi Mi Note 2 still does take some fairly good pictures, however it leaves us wondering what the experience would have been like if Xiaomi had gone with an image sensor that has PDAF, like the Sony Exmor RS IMX258 (which they use for the rear cameras in the Mi 4c, the Redmi Pro, and the Mi 5S Plus) instead of the Sony Exmor RS IMX268.

There are four video quality options for the rear camera (4k, FHD, HD, and SD, all at 24 Hz) and only one for the front camera (FHD at ~17 Hz), all of which record in H.264. While the Snapdragon 821 is capable of hardware accelerated HEVC encoding, it is understandable that Xiaomi decided not to use it, both because of the substantial licensing costs, and the lack of support for HEVC from most media players and web browsers. With the Qualcomm Snapdragon 835 joining Samsung and Intel in offering VP9 hardware accelerated encoding, hopefully we will soon see OEMs start to offer the option of recording in VP9 (and eventually it’s successor, AV1). Until then however, H.264 and VP8 still are the best options.

That being said, the choice to limit recording with the rear camera to 24 Hz is a bit disappointing, especially when the camera sensor itself is capable of 4k 60Hz HDR recording and full resolution 30 Hz HDR recording (thanks to the use of Sony’s SME-HDR technology which we detailed in our breakdown of the Google Pixel’s camera, the Sony Exmor RS IMX378), and the Snapdragon 821 is capable of recording at 4k 30Hz. It would have been nice to see higher frame rates at FHD at the very least, if not at 4k as well. Similarly, the front camera sensor is capable of 4k 30 Hz HDR and FHD 60Hz HDR, so to see it limited to FHD ~17 Hz is decidedly disappointing.


Display

The Xiaomi Mi Note 2 packs a 1080p 5.7-inch curved LG P-OLED display. While it is a perfectly acceptable resolution, the RB-GB 1080p layout is noticeably lower resolution than the RGB 1440p displays found in flagships like the HTC 10 and LG G5, let alone something like the 4k display found in the Sony Xperia Z5 Premium.

It is quite interesting to see an LG P-OLED display in a phone instead of the usual LCD or Samsung AMOLED displays that we see elsewhere. Most of the differences between the P-OLED display and comparable AMOLED displays seem to be fairly miniscule, with them even using a similar PenTile-style diamond subpixel arrangement, however there is one key difference. Instead of being laid out in an RG-BG fashion like Samsung’s displays (which Samsung claims is done to maximize the green subpixel resolution as our eyes are most sensitive to green), LG uses an RB-GB layout that maximizes the number of blue subpixels. While an official reason has not been given for the difference, blue subpixels currently degrade the fastest and use the most energy, largely because they were invented the most recently and haven’t had as much time to be optimized and improved. LG may have chosen the RB-GB layout to help minimize those issues.

At around 350 nits, the Xiaomi Mi Note 2 is bright enough for most scenarios, however it falls substantially behind most current flagship devices, and can be difficult to read in direct sunlight at times as a result. This problem is only exacerbated by its lack of a sunlight brightness boosting mode, such as the one that Samsung uses for their AMOLED phones.

In addition to its low maximum brightness setting, the Xiaomi Mi Note 2 has a relatively high minimum brightness setting as well. The display is far too bright for use in bed, easily waking other people in the room. This issue could have been partially abated through the use of Android’s new Night Light feature, however the Xiaomi Mi Note 2 does not yet have it because the device is only on Android 6.0 (which highlights the need for updates to the underlying Android version, in addition to the frequent MIUI skin updates). The phone does have a “reading mode” which tints the screen yellow when in certain apps, however it still remains quite bright, cannot be set on a timer, uses a particularly irritating shade of yellow, and overall just doesn’t work nearly as well as Night Light.

In the default “Automatic Contrast” colour mode, the whitepoint on the Xiaomi Mi Note 2 trends very blue, and colour accuracy suffers to some degree. Thankfully there is a “Standard” colour mode which has much more accurate colour reproduction, although the whitepoint is still bluer than it should be.

Viewing angles are fantastic with very little colour shift even at extreme angles, although the curved edges do see some luminance falloff when you aren’t looking at the device headon.

It is a bit disappointing to see that the Xiaomi Mi Note 2 targets the NTSC colour space instead of sRGB (bragging about having 110% NTSC coverage), as it currently causes compatibility issues which we have explained in-depth previously. Android still lacks system level colour management, which means that the vast majority of the images you see (including ones taken with the phone itself) will be displayed inaccurately due to them targeting the sRGB colour space, so content colours will be displayed conformed to NTSC with mistagged colour data.

That being said, Xiaomi are far from the only ones with this problem, with Samsung and LG running into even harsher versions of this issue with their support for HDR displays and the DCI-P3 colour space (respectively). This is an issue that will take system level changes to Android to fix, and it will not be an easy fix at that. In the meantime, those of us who want colour accuracy are stuck relying on sRGB modes. Thankfully, Android will be becoming colour space aware with Android O, which should help alleviate these concerns down the road.


Battery Life & Charging

Battery life on the Xiaomi Mi Note 2 is fairly good, but a bit disappointing when looking at just the hardware. The 4070 mAh battery is above average for a 5.7” phone, but in terms of actual performance it is just average.

Xiaomi Mi Note 2

PCMark 2.0 Work Battery Life

Min. Brightness

9 h 43 m

Med. Brightness

9 h 0 m

Max Brightness

6 h 12 m

While 6 hours on maximum brightness and close to 10 hours on minimum brightness are both quite good, it is a bit disappointing to see from a phone with a 4,070 mAh battery. In our test of the 3,450 mAh Pixel XL, we saw similar results despite the Xiaomi Mi Note 2 having an 18% larger battery and a lower resolution (albeit slightly larger) display. While there are some surprisingly substantial differences in efficiency between the two models of the Snapdragon 821 SoC, the differences in the expected battery life of these two phones is more than what can be explained by the SoC alone, and indicate higher power drain from other parts of the device as well. Notably, the OnePlus 3T (which shares the same SoC as the Xiaomi Mi Note 2) saw over 9 hours on minimum brightness in the same test, despite having just a 3,400 mAh battery.

Thanks to Qualcomm Quick Charge 3.0, charging times remain fast despite the large battery. The phone takes just under 2 hours to go from five percent to a full charge.


Audio

Xiaomi Mi Note 2 Audio Settings

The Xiaomi Mi Note 2 has a single bottom firing speaker, but it gets surprisingly loud, even outpacing phones like the HTC 10. While the speaker does get quite loud, the audio quality takes a step back from what you would expect from a flagship phone. The speaker has multiple issues with audio quality, that can completely change the way a song sounds. It has a bit of a smeared sound to it, with fairly poor transient response, resulting in the notes at the beginning of The Weeknd’s Starboy rolling together. The bass is also quite muddy, which shows up to a comical degree in Drake’s Back to Back. Even with those issues however, the speaker still performs at an acceptable level, and should be sufficient for people who only occasionally use their speakers for music. Audio reproduction in the vocal range is adequate, which should be enough for use in speakerphone mode, where the speaker’s high volume can be useful.

The headphone audio and microphone recording are both entirely unremarkable. They will do the job and sound just fine on most headphones, but they are not anything to write home about either. The Xiaomi Mi Note 2 performs at the level that would be expected from a standard Qualcomm Snapdragon 821 based smartphone thanks to Qualcomm's Aqstic hardware, and that is just fine.

Developer Relations

Developer relations is unfortunately an area with Xiaomi has consistently fallen short historically, although they are working on it.

Earlier this year, Xiaomi finally released the kernel sources for the Redmi 3S, 3X, and 3S Prime, which is always good news (even if it was seven months late). What was disappointing to see was that they didn't publish it until someone spammed their forums and github issue tracker asking about it, at which point they almost immediately released the kernel sources. That would indicate that it was either ready for release (as it should have been when the device itself released), or they had left it so close to being ready that they could finish it up in a couple hours (likely the former, as the most recent commit to the branch was weeks earlier). The Xiaomi Mi Note 2 saw a similar delay, with the kernel sources not being released until April 26th, half a year after the phone itself officially launched.

Delaying the kernel source release like that is just plain old anti-consumer behaviour which delays the development of custom ROMs, and prevents the community from submitting patches that could help Xiaomi. It is incredibly disappointing to see behaviour like this from one of the world's largest phone manufacturers, and we sincerely hope that Xiaomi will try to break this trend of copyright violations that they currently have.

Xiaomi relatively recently started requiring approval from them to initially unlock your phone’s bootloader, which they announced was an attempt to curb the number of resellers who had been unlocking the bootloaders of Xiaomi phones, and selling them with alternate ROMs pre-installed (some of which contained bloatware). The announcement came right after Google announced an Android-wide feature, Verified Boot, that would prevent the same thing without needing to contact the manufacturer. Xiaomi’s solution is a bit stricter (as it completely prevents you from unlocking the bootloader, instead of just giving a warning message on reboot), however it does bring two major problems with it. Namely, that there is a limit on how many devices you can unlock per year (which can be problematic if you switch phones often, or if you have to deal with a warranty replacement) and you have to actually contact them for the unlock code (which is problematic because 1. it can potentially take a couple weeks for them to process your unlock request and 2. if they stop processing unlock requests for your phone model for any reason, then there would be almost no hope of unlocking the bootloader).

Interestingly, on our testing unit, unlocking the phone’s bootloader did not factory reset the device. This is a bit worrying, as wiping the user storage is a standard part of unlocking a phone’s bootloader, and is done for security purposes. If the phone does not wipe a user’s internal storage when unlocking the bootloader, then whoever unlocks the bootloader can potentially access the files on the phone.

Once the bootloader is unlocked, it can be locked and unlocked straight from fastboot. There was no “OEM unlocking” security setting in the developers’ menu like many recent Android devices have to lock it down further by requiring the device’s password to re-unlock the bootloader. This setting could have helped provide some extra reassurance for those who have unlocked their devices, and is sorely missed.


Final Thoughts

The Xiaomi Mi Note 2 is another fantastic device from Xiaomi, with a few rough edges that need improvement. It is a definite step in the right direction, but Xiaomi still has quite a distance to go if they want to have a device that can truly go toe to toe with the competing flagship phones from the likes of Samsung, HTC, LG, and Sony. In the meantime, the Xiaomi Mi Note 2 is a solid choice for a near flagship experience at a cheaper price, especially if Xiaomi continues to smooth the bumps out of their software experience.

While the camera experience on the Xiaomi Mi Note 2 is a bit lacking and Xiaomi still struggles with developer relations, the fluid UI, great battery life, and fantastic frequency band support make for a compelling device.


We would like to thank Gearbest for providing our review unit. You can find the Xiaomi Mi Note 2 and other smartphones available for sale on their website with shipping to numerous countries.