Table of Contents
Xiaomi Mix 4 Review
1. Preface and History
A few years ago, Xiaomi phones are still synonymous with value for money, which is also the brand’s brand. 1999 yuan (about 20,000 INR), Xiaomi since the release of the first cell phone, is known for its cost-effective smartphone circle. With a unique Internet operation, minus the cost of the dealer, but the same, cost-effective has become a constant for Xiaomi phones.

Xiaomi has an important premise of cost-effectiveness, making Xiaomi dare not invest in a lot of research and development, especially in the high-end market, Xiaomi is much less, at the time, no one would want to buy a 5000 yuan Xiaomi smartphone. Such a cycle would make it difficult to break the ice.
In early 2015, the main high-end flagship Xiaomi Note debuted, the top version of a very rare 2K resolution screen, priced at 3,299 yuan, and invited celebrity endorsements, still in ignorance of Xiaomi, released a series of positioning high-end.
The final reaction is also known, the performance is not satisfactory, the most important point is that the tone of the Xiaomi brand has not yet been established, almost without any warning released Note series, coupled with the product is a heap of material, ignoring the experience.
In 2016, Xiaomi Note 2 launch, Lei Jun only spent half an hour talking about the model, when everyone thought the launch was over, the big screen appeared MIX, when the moment of lighting up the screen, the whole room rejoiced. It is jubilant, the author was squatting by the computer to watch the launch, impressed.

At that time, the smartphone faced a choice, which form should be developed, is folded? Is the flip? Xiaomi MIX’s initial generation answered – full screen, then many years later, the smartphone screen ratio began to expand, from 18:9 ratio to notch screen, then to the water drop screen, and then the punch-hole screen.
A Finnish National Design Museum curator said this about the initial generation of Xiaomi Mi MIX, which pointed to the future direction of smartphone design.
In the following years, Xiaomi laid out the high-end market, one after another released the MIX 2/2S, until the MIX 3 in 2018, this series pressed the pause button, began to focus on the digital series, and the Redmi brand-independent, the latter took over the cost-effective flag, Xiaomi is impacting the high-end market, the results you all know, with the Xiaomi 10 series, Xiaomi 11 series, the brand has gradually gained a firm foothold in the high-end market.
During this period, although there are also MIX Alpha, MIX FOLD these models released, but are not part of the basic sequence, Mi fans heart, is still the iteration of the update – Xiaomi MIX 4.
Now, it is here, Xiaomi Mix 4 Review
2. Xiaomi Mix 4 Specifications
Model | Xiaomi Mi MIX 4 Full |
---|---|
Display | Size: 6.67-inch CUP full screen, Type: AMOLED material, Resolution: 2400 × 1080, Support P3 color gamut, JNCD * 0.34, dE = 0.40, 480HZ touch sampling rate, Contrast ratio: 5000000:1, 10bit color depth, Support front and rear ambient light sensors, Corning Gorilla Glass Victus, Supports True Tone true color display, Dolby Vision and HDR10+ |
Processor | Qualcomm Snapdragon 888 Plus Frequency up to 3.0GHz, and the total 23% AI computing power increased |
Storage | RAM: LPDDR5 6400Mbps ROM: UFS 3.1 |
Heat Dissipation | 1206mm² Large area + 3D graphene uniform temperature plate + 4932mm² Mid-frame dual 40um graphene + 5150mm² dual 40um graphite |
Rear Camera | 108MP HMX Main Camera, 1 / 1.33″ outsole, 1.6um four-in-one fusion large pixels, Support OIS optical image stabilization, 7P lens, equivalent 24mm focal length; 13MP free-form super wide-angle camera, FOV120°, 6P lens, equivalent 12mm focal length; 8MP periscope telephoto lens, 5X optical zoom , support OIS optical image stabilization, Equivalent 120mm focal length. |
Front Camera | 20MP CUP screen front camera, 1.6um four-in-one fusion large pixel |
Connectivity | UWB: One finger connection, Multi-function NFC chip, door card simulation, Support infrared remote control |
Battery | 4500mAh Capacity MTW multi-pole battery cell |
Charging | 120W fast wired charging in 15 minutes to 100% 120W constant temperature charging in 21 minutes to 100% 50W wireless second wireless in 45 minutes to 100% Fast wireless charging to 100% in 28 minutes* |
Audio | 1014 super linear upper speaker, 1216P super linear lower speaker, Harman Kardon professional tuning stereo dual speakers, Hi-Res Audio certification, Hi-Res Audio Wireless certification |
Motor | X-axis linear motor |
Colors | Shadow Green Gray, Ceramic White, Ceramic Black |
Size And Weight | 162.65 × 75.35 × 8.02mm 225g |
3. Design and Build
Color scheme, Xiaomi Mi MIX 4 provides Ceramic Gray, Ceramic White, Ceramic Black three color schemes, all using unibody full ceramic body, and the first lightweight one-piece precision ceramic, what is there? Come see the picture appreciation.




After removing the phone protective film into the phone, it looks like a block of glass, here to say Xiaomi MIX 4 with dual-curved screen form, but some users still like the straight screen, some say the curved screen is easy to accidentally touch, some say not as good-looking as the straight screen, but for now, MIX 4 this slightly curved form, very suitable for the moment, and personally think that the rest screen face value is higher than the straight screen (Everyone has their way of looking at it, anti-bar). While MIUI also has an algorithm to reduce the curved screen mis-touch, which will be discussed later.


This screen is the most important part of the MIX 4, using a new CUP full-screen, claimed to be after three generations of technology iterations, the photo area, and display area all reach 400ppi. Whether front or side or other color display, are completely invisible. To the centered lens (centered in the more obvious area is the original protective film digging holes), the actual screen complete display.


To achieve this display effect, Xiaomi Mi MIX 4 pioneered the micro-diamond arrangement, maintaining the number of pixels and RGB ratio unchanged, reducing the sub-pixel area, reducing light-blocking, to achieve 100% full pixel display. There is a unique circuit design, ITO transparent lead, compared to the initial generation shown last year, there are still mosaic, screen, pixel density, and other issues. This time, the Xiaomi MIX 4 screen, in-display effect, really achieved a high degree of unity of the normal screen.

The CUP display area of 0.2cm², occupying 0.2% of the entire screen area, is said to be such a small area, but the cost is more than a whole conventional flagship screen, the cost has increased significantly, and the production process is complex.
Parameters, MIX 4 this screen is 6.67 inches, AMOLED material, the resolution is 2400×1080p, support P3 color gamut, JNCD ≈ 0.34, dE ≈ 0.4, HDR10+, support 120Hz refresh rate + 480Hz touch sampling rate, 10bit color depth, and True Tone true color display, dual front and rear sensors, Corning Gorilla Glass Victus, Dolby Vision.
After checking, Xiaomi this screen from Huaxing Optoelectronics, to be precise, Xiaomi and Huaxing joint research and development. According to the official introduction, they invested a hundred people, a special team, taking 3 years, the total investment cost of more than 500 million yuan, and applied for more than 60 patents including high transmittance screen design, underlying software self-research algorithm.



How to evaluate this screen? Before saying that, let’s talk about an important issue, that is, the conflict between under-screen and lifting front camera, both achieve a full-screen without openings, both can display a complete screen, but the latter due to the mechanical structure, increase the weight and thickness, and occupy inches of internal space, said to be more appropriate for the transition, the under-screen camera is in line with the law of upgrading, from bangs to water droplets, and then from the dugout to under-screen.
First of all, although there are already models of under-screen cameras on the market, from a visual point of view, MIX 4 this program, is the most excellent under-screen camera display I’ve seen so far, no one, to do and other screen areas display the same.
Regrets, of course, is the quality of the screen, now the flagship models are basically high resolution + high refresh rate, including peak brightness, color accuracy, the panel have a very high level, such as Xiaomi 11 Ultra, belongs to the top ranks, and under-screen camera or new technology, hard to say that it is the top display that is certainly bragging, but as said earlier, Xiaomi MIX 4 display effect, to my personal view is completely adequate.
Design, MIX 4 rear for the rectangular camera module, located in the upper left corner, belongs to the conventional shape, no Xiaomi 11 Ultra as unique recognition, the overall is still the Xiaomi design language of the past two years, can only be said to be moderate, not too bright, just when I was a little disappointed with the design, held in the hands but changed the view.
It gave the author the first feeling of MIX 2 full ceramic texture, careful observation found that it is indeed Unibody’s full ceramic body and the debut of a new lightweight one-piece ceramic.
In Author’s impression, the traditional ceramic is not used on a large-scale cell phone, in addition to the cost is higher than glass, and then the weight, but there is one, ceramic warmth like jade texture, is incomparable with glass or other materials.


But the MIX 4 is not that heavy in the hand, the bodyweight is only 225g, which is similar to some flagship models made of glass. The reason for this is due to the machine’s lightweight ceramic. The use of high-purity nano-zirconia composite material, this terminology is difficult to understand, as long as you know that compared to the traditional ceramic light 30% weight on the line, but still the original texture of ceramic.
Xiaomi side, Xiaomi MIX 4 lightweight one-piece ceramic production process is quite complex. Compared to traditional ceramics 25% more, requiring 46 processes. If there is a hair’s breadth of difference, then the entire furnace ceramic is all scrapped, I have to say, this is another exploration of the MIX. This series of the ceramic process, not blowing not black, for the full ceramic body + body of various components, MIX 4 to do the acceptable weight.


Porcelain has a long history, dating back as far as 3,000 years ago, China already has porcelain, and in the Song Dynasty is divided into five famous kilns, so for the national people, ceramics is a symbol of a long history, gentle and elegant.
Color, Xiaomi MIX 4 in addition to Ceramic Black and Ceramic White, and then is this Ceramic Gray, said to be inspired by the traditional ceramic treasures of the Northern Song Dynasty shadow green porcelain, the tone is greenish light blue, like a diamond.
To achieve this color scheme, the machine uses a high-purity nano-material formula, supplemented by niobium oxide rare earth metal oxides and a variety of metal oxides as colorants, and then dissolved, precipitation, high-temperature calcination, and other processes, resulting in this color scheme now, looks like some chaotic, but look closely but has a translucent texture.


I know a little layman like this, firing ceramics is the most difficult light color, like the gray, the process can not have any impurities, a little carelessness will be a thousand miles, someone may ask, why white on it? This is because most of the ceramics after firing, the original color is white, so the firing process of shadow blue-gray, I think it is much more difficult.
Maybe you guys also see, before the author review Xiaomi Mix 4, no one has such a detailed body introduction, this is because in my hands, MIX 4 really let me feel a sense of artwork, so talk more, but just say useless, there is time to go offline experience the real machine, hands certainly stunning, especially the delicate feel of ceramic.







In addition MIX 4 also makes up for the Unibody all-ceramic body a shortcoming, is the signal, ceramic has a very strong hardness, antenna band how to do? The author found a point of care Xiaomi designers, MIX 4 screen and bezel in the middle of a small A shell (face shell), generally cushion the phone fall screen broken, and Xiaomi MIX 4 to A shell made of metal, look carefully, you can see the antenna of the small narrow strip hidden inside.

4. System Experience
The MIX 4 in the author’s hands is running the Android 11-based MMIUI 12.5.3, which has been said many times before in Xiaomi phone reviews. Here are a few MIX-exclusive features, as well as some of the new MIUI features.

In terms of features, this screen is complete, such as DC dimming, eye protection mode, color style are retained, and support for 120Hz refresh rate, while supporting the AI master image quality engine, with super-resolution enhancement, video image quality enhancement, dynamic screen compensation, and other display features.

The system has a built-in setting called edge anti-touch, mainly to reduce the double-curved surface brought about by accidental touch, there are three modes to choose from, support custom area size. Some previous waterfall screen models also have this feature, the actual use of obvious results.

MIX 4 charging support wired/wireless fast charging, including four charging modes, the default is the regular constant temperature charging, there is also a sprint charging mode, as well as wireless charging 50W, 100W mode, this part is described in detail later.
The machine has a new intelligent charging system that is claimed to extend battery life by 25%, which are night intelligent charging mode, time-domain intelligent charging mode, and battery health display. Among them is the night smart charging is to solve the night time charging when sleeping, to avoid battery full charge.
For example, if you charge your mobile phone before going to bed, it is fully charged in 1 hour, and the remaining few hours are fully charged, which affects battery life. Therefore, the algorithm of MIX 4 is that if the user is detected to sleep, then the mobile phone just charges up to 80% smartly, and then according to the alarm time, the user will be fully charged when the user is about to wake up. It is an AI learning aid. It will not be felt in a day or two. It is estimated that it will take half a month to learn.

As much as the wind security, in addition to the previous flares, hidden masks, etc., mainly new anti-loss function, officially known as the strongest anti-loss mechanism in the history of Xiaomi.
The main functions are divided into five, not shutting down, not breaking the network, not leaking, not being stolen, not compatible with other cell phone cards. In the case of triggering the lost mode, not shutting down the phone means that the lock screen shutdown requires verification of the password, the regular operation.
Interestingly, the network does not stop, we all know that the phone is lost and disconnected when the card is unplugged, the function of finding the phone is equivalent to waste, and the MIX 4 has a built-in virtual SIM card, even if the card is unplugged can be located, automatic networking, the traffic generated is completely free.
If it is not stolen, the SIM card is bound to the mobile phone and can only be used after unlocking, and after binding, the mobile phone is not compatible with other mobile phone cards, so it can only be used after unlocking. In other words, as long as the Mi MIX 4 has power, the loss location can be achieved. So the question is, what should I do if the battery is removed directly? So this feature feels more of a gimmick, it’s better not to lose the phone.

Finally, an advertising word, before the author said many times the built-in App ads, MIUI 12.5 latest version reduces many, such as weather, calendar, etc., the bottom of the ads are gone, I hope that in the future less and less it.
5. Performance
The core configuration, Xiaomi MIX 4 first equipped with Snapdragon 888 Plus processor most users are familiar with, compared to Snapdragon 888, the main upgrade Cortex-X1 large core, its main frequency from 2.84GHz to 3GHz, while the AI engine by pulling up the frequency and software optimization to achieve a comprehensive performance improvement, arithmetic power of 32 trillion operations per second (32 (TOPS), AI performance improved by more than 20%.
From the previous performance of Snapdragon 888, the performance belongs to the absolute flagship, but the power consumption and heat are somewhat unsatisfactory, while Snapdragon 888 Plus instead again boosts the frequency, its power consumption is expected to be even higher, and the MIX 4’s response plan is to add a balanced mode.

The official introduction, the balanced mode will limit the phone’s energy consumption, to control heat purposes, to put it bluntly, is to the processor to reduce the frequency, turn on the performance mode is to release performance, is a common practice in the industry to control the temperature, according to Xiaomi official data, open balanced mode of the MIX 4, than the Snapdragon 888 cell phone temperature is even lower.
Another is the recently added memory expansion, the MIX 4 can be expanded by 3GB of running memory, calling some of the unused ROM space for RAM operation, boosting the equivalent memory capacity, and integrating RAM and ROM through algorithmic optimization.
In addition to Snapdragon 888 Plus, the machine also has a fully-optimized version of LPDDR5 memory + UFS 3.1 flash memory, as well as the first 3D graphene homogeneous plate, which is graphene made of 280 microns thick homogeneous plate, compared with the previous homogeneous plate, thermal conductivity is more efficient, the area is 1206mm², the processor and motherboard periphery are covered.


After the Xiaomi Mix 4 AnTuTu Benchmark actual test, it running score of 830506, where the CPU and GPU scores are higher than the ordinary Snapdragon 888 models, pulling up the frequency derived from the performance, a small upgrade. In terms of storage Xiaomi MIX 4 is equipped with UFS 3.1 flash memory, sequential read speed of 1950MB/s, sequential write speed of 737MB/s.
6. Camera
The camera, Xiaomi MIX 4 is more conventional, compared to the current flagship models, such as their own Xiaomi 11 Ultra, can only be said to be moderate, but the overall performance is better than Xiaomi 11, with an additional telephoto lens.
Parameters, Xiaomi Mi MIX 4 rear for 108-megapixel main camera (HMX, 1/1.33 inches, OIS optical stabilization) + 13-megapixel free-form ultra-wide angle (FOV 120°, 6P) + 8-megapixel periscopic telephoto lens (5X optical zoom, OIS optical stabilization).
How the specific performance, look at the sample photos. It should be noted that because the Author is in an area for epidemic prevention and control, so he does not go out to shoot high-rise buildings, only in a small area to simply shoot, I hope to understand.
Daytime Samples







Among them, the free-form lens can achieve a large field of view of 120°, hardware-level anti-distortion, an ultra-wide-angle lens with a new set of algorithms, after enabling the ultra-wide-angle lens, the main camera will also be shot, the two photos are merged into one. It is the main shot, and the edge is the ultra-wide-angle shot, maintaining the resolution of the photos.
Nighttime Sample






Judging from the Xiaomi MIX 4 camera samples, the algorithm is still the dark part brightening and highlight suppression used by Xiaomi. The night scene mode is changed to take multiple shots and then perform calculations, but the effect is better than the previously evaluated Xiaomi 10, which is the latter. Now that the algorithm has also come up, it is foreseeable that in the future mobile phone cameras will begin to develop computational photography, rather than a thoughtful outsole and high-resolution.
7. Battery life and charging
Xiaomi MIX 4 built-in 4500mAh battery MTW multi-pole battery cells. Since the installation of higher frequency Snapdragon 888 Plus, so how will the power consumption performance? Use the AnTuTu stress test function to conduct a superpower consumption test.
The stress test is a function built into the AnTuTu review to test the stability of the device’s performance by performing high-load calculations, which requires the CPU to perform a large number of calculations, so the power consumption is greater compared to video, daily use, and other scenarios.
Test conditions: no SIM card inserted, device connected to Wi-Fi, positioning turned on, fully charged, screen brightness turned to the highest, and all background services turned off. Open the AnTuTu stress test, uninterrupted testing, and record the remaining power of the device every 30 minutes.

Under the Super Power Consumption Test, Xiaomi Mi MIX 4 battery lasted 180 minutes, comparable to the Snapdragon 870 model (4500mAh) last reviewed, most notably due to the new Balanced Mode, which controls power consumption and body heating with frequency reduction, making the MIX 4 last even longer than some Snapdragon 888 models. And impressively, the machine consumed only 9% of its power in the first 30 minutes of the stress test.
Finally, the endurance estimate, as this result is obtained based on the CPU being at full capacity all the time, taking into account our daily use and bright screen time, so this figure has to be converted to a multiple, resulting in the MIX 4 being able to have more than 6 hours of continuous use, note that it is continuous use, not daily screen off, return messages, etc.
Charging is a traditional strength of Xiaomi phones, almost every flagship has a breakthrough, Xiaomi MIX 4 is to reach 100W wireless fast charging, but the default is 50W, you need to manually open the 100W charging mode.
Wired, the default is 120W wired fast charging, but not continuous high power, the same provides a manual open option, after opening the boost mode, to play the full speed of 120W.

After the actual test, Xiaomi Mi MIX 4 constant temperature mode 21 minutes to 100%, including 9 minutes to charge 55% of the power, the boost mode, 120W fully released, 15 minutes to 100%, 9 minutes to charge 72% of the power.


Then we look at wireless charging, which requires a Xiaomi 100W sailboat air-cooled wireless charging dock, and a 120W charger. Wireless mode is divided into two modes of 50W and 100W, of which 50W wireless charging takes 48 minutes to charge to 100%, 100W wireless is 29 minutes to charge to 100%, the speed directly doubled, beyond most wired charging speed.
8. Xiaomi MIX 4’s road of exploration
Before the release of the MIX 4, it took more than 1,000 days, however, the project was established at the end of 2018, which means that Xiaomi polished for nearly three years.
Three years to polish a model, behind the pay can be imagined, that is, this expectation, coupled with the initial generation of stunning, so that the MIX 4 invisible expectations pulled too high, although its performance is absolutely in line with the meaning of exploration, after giving the MIX series, it seems that there is not too much innovation?

To say this, we first put aside the CUP full-screen, lightweight one-piece ceramic, look directly at the product itself, paper parameters, MIX 4 equipped with Snapdragon 888 Plus processor, the rear is still 108MP main camera, 120W wired charging + 100W wireless charging, belonging to the regular update.
So what is the significance of MIX 4 exploration? It is “internal strength.” Lei Jun has mentioned many times that Xiaomi high-end mobile phones will have to experience the experience. For now, the author believes that it is necessary when needed, such as mobile phone signal, and then temperature control. Xiaomi’s previous style can only be described as 120W full-speed charging, but this time it has specially added a constant temperature mode, as well as a balanced mode and anti-lost function.
Doing all this is to make the MIX 4 more practical, rather than just piling up parameters to make the data look good. It can be said that it is different from all previous MIX series models and based on exploration (CUP full screen, lightweight ceramic), it starts to focus on user experience.
The author got the MIX 4 for a few days, the front of the test is done, but the final summary of this piece of delayed writing, the reason is that author do not want to prematurely conclude, so after watching the launch and look at the views of many users of the MIX 4, a problem is the MIX 4 configuration is not as good as the Xiaomi 11 Ultra?
In addition to the normal upgrades, image capabilities are indeed not as good as the Xiaomi 11 Ultra, as, for selfie camera performance, Lei Jun even confessed that the current under-screen front camera is not as good as the dugout, but to know the MIX 4 also has the above characteristics, it can only be said that the two positionings are different, each has its advantages. Throughout, the Xiaomi digital series lies in the breakthrough, from 1 to 2 or more, and MIX lies in innovation, from 0 to 1.

Finally say a digression, Lei Jun annual speech, talking about a past, 2014, the first World Internet Conference, when Lei Jun said with great enthusiasm Xiaomi to do the world’s first, was mocked and laughed, almost everyone thought impossible, now Xiaomi did the world’s second (2021 Q2), so when Lei Jun said within three years, Xiaomi cell phones to achieve the first in the world, no one ridicule, no one even questioned.
Seriously, every time I see Lei Jun online, it’s hard to imagine that he can make Xiaomi cell phone the second in the world within 10 years, completely changing the rules of the cell phone market, just like the MIX series, always on the road of exploration, brave and passionate.
Note: Original article published on AnTuTu Benchmark by author Tangzheng.