The Xiaomi Mi Mix 3 was recently announced in Beijing and was initially geared towards the Premium market. At publishing time, the Mi Mix 3 was priced at ~$475 USD for the base model. We covered the Mi Mix 3 launch event earlier, and now it’s time for the review based on our hands-on experience. We will finalize it when the retail unit arrives at the office.

With price and screen size as main selectors, we got a good number of cellphones which will be used to assess how the Xiaomi Mi Mix 3 fits in its immediate smartphone landscape. We’ve added popular high-end phones since many people want to know how the Mi Mix 3 competes with them.

Our list: Xiaomi Pocophone F1 (~365 USD), Huawei P20 (~525 USD), Samsung Galaxy S8+ (~545 USD), OnePlus OnePlus 5T (~430 USD), Apple iPhone XS Max (~1099 USD), OnePlus OnePlus 6 (~529 USD), Samsung Galaxy Note 9 (~840 USD).

This smartphone feels comfortable in hand because it has a width of 74.7 mm for a thickness of approximately (0.33 inches, 8.5mm). For reference, this is based on a medium size hand (US M gloves), and you can try extrapolating from here.

The weight of 218 grams (7.69 oz) makes it a heavy smartphone, although it surprisingly doesn’t feel *that* heavy, perhaps because of its shape and surface area. The amount of battery capacity the customer gets is good for a phone of this size. The screen display-to-body ratio of 85.0% is also excellent overall.

Note that Ubergizmo uses its own method to compute this ratio, and we use it across our reviews for consistency across all brands, since each may use different calculus formulas. The official screen ratio from Xiaomi is 93.4%, although we’re not sure which formula has been used to calculate this value.

Key technical specifications

Xiaomi Mi Mix 3
Display6.39” AMOLED Display (2340×1080)
Camera
  • Main: 12MP Camera, f/1.8, OIS + 12MP 2X zoom, f/2.4, EIS
  • Selfie: 24MP, f/2.2, fixed-focus, pixel-binning
Processor, RAMQualcomm Snapdragon 845 platform with 6, 8 or 10 RAM
Storage128, 256 GB (no microSD)
Battery3200 mAh battery capacity
OSAndroid 8.1

Design

The original Mi Mix smartphone was created to march towards a full-screen handset, and much ground has been covered since. Mi Mix 3 is yet the best step towards this end-game. As other Mi Mix before it, this handset has an aluminum rim on the side and a ceramic back. The front is hardened glass, of course, to protect from scratches.

Besides looking very neat, the highlight of the design is the sliding mechanism that pulls the display down by a bit less than 1cm, revealing the dual-camera selfie system -with LED flash- a very rare feature that hardcore selfie or vlogger may appreciate even more than the lay person.

We were wondering how strong the mechanism is, and it turns out that Xiaomi is using magnets instead of springs to provide such a satisfying clicky feel upon sliding. It’s great because it should be much more durable this way and the company says that it ran tests with 300,000+ open/close cycles.

Fortunately, Xiaomi managed to build a slider chassis that has the same thickness as the Galaxy S9+ (~0.85 mm) and is, therefore, free of compromise about size. For people who don’t use the front camera often, nothing will be missed, and for those who do, the sliding action will start the selfie cam automatically, so it’s actually faster than conventional phones.

"SUCH A SATISFYING CLICKY FEEL UPON SLIDING"

The slider action is, in theory, programmable, but we’ll have to see how many options people will have. It would be nice to answer/terminate calls with it, and we already know that apps can open/close menus/actions with it. It probably requires additional coding.

As a result, using a sliding mechanism doesn’t remove something critical, and might even enhance the experience. A downside to the slider might be that the battery capacity can’t be the highest because the total device volume might not be used optimally. Another one it is more challenging to have waterproofing with these moving parts.

It is important to note that there is no 3.5 mm audio connector. Although it is generally better to feature one, many customers don’t mind not having it since they have switched to wireless headphones. For others, a USB-C to 3.5 mm adapter works.

Overall, the Xiaomi Mi Mix chassis is an excellent piece of engineering, and the special Forbidden City edition is absolutely beautiful, in addition to having 10GB of RAM.

Durability

The back cover is made of Ceramic, which is less prone to cracks than glass and much harder to scratch than aluminum. It is still possible to crack it, so avoid drops or use a case.

After considering how the smartphone was designed, we estimate that the odds of breaking during a drop on a hard surface as probable. You can refer to our general article about how phones could be designed to avoid cracks on impact: How the LG V20 Was Designed To Survive Drops

The Mi Mix 3 has not received a U.S Military MIL-STD 810G certification or an IP rating for water and dust protection. Although this is not uncommon in the sub-$500, some handsets are better protected from water (Huawei P20), which is a leading cause of smartphone death.

Display

As the Star of the show, the beautiful Mi Mix 3 display had to be OLED powered, but interestingly, image quality was not the primary driver behind this decision. OLED displays are also thinner, and according to Xiaomi’s CEO that was key to make the phone’s chassis just as thin as the Galaxy S9+.

It’s true that the resolution of 2340×1080 (403 PPI) isn’t nearly as high as the 2960×1440 pixels seen on Galaxy Phones (~515 PPI). However, this is a classic trade-off for phones that are designed to compete in price.

"EASILY OUTPERFORMS LCD-BASED COMPETITORS"

There are excellent reasons to want a higher PPI display, such as seeing more details in HD photos, and better-defined text. However, this is not something that people complain about often, or would be willing to pay hundreds of dollars more to get.

At a glance, the Mi Mix 3 display is very good and easily outperforms LCD-based competitors. However, in the phone line-up we looked at, 6 out of 8 phones use OLED displays, so you can see where this is going.

Display technical analysis

The Mi Mix 3 display has a Samsung AMOLED panel. OLED is an entirely different display technology (than LCD) that has been widely present in smartphones. The fundamental difference between OLED and LCD displays is how light is emitted.

With LCD, there is a small number of white light emitters (1-2 for handsets, 2-100 for TVs) and black pixels are created by “blocking” the white light with a filter. Unfortunately, using a filter leads to “light bleeding” and “black color” that is in fact, dark-gray.

With OLED, every pixel emits its own light. This also means that creating a black pixel means merely leaving it OFF. As a result, black color is actually black, and other colors are more straightforward to control without using complex filters and color control technologies such as Quantum Dots and Nano Dots. You can read our complete LCD vs. OLED article which goes deeper into the details.

The resolution of 2340×1080 would be considered to be high in absolute terms and compared to the competition it would be plain since a ~400 PPI pixel density is really common for this market…

Mi Mix 3 Camera

Bright light photography

Xiaomi Mi Mix 3

Galaxy S9+

The Mi Mix 3 camera system is using cutting-edge components (more on that below), and this shows in the photo samples we’ve taken so far.

"THE MI MIX 3 HAS NO PROBLEM COMPETING WITH THE BEST CAMERA PHONES"

In daylight conditions, the Mi Mix 3 has no problem competing with the best camera phones such as the Galaxy S9+. Our casual side by side photo comparison show this, with no clear winner. You would have to look really closely at small details that can be explained by small variations in metering or white balance.

If anything, the S9+ has a small tendency to over-expose to make the photo brighter, even in daylight, while the Mi Mix 3 will be a bit more conservative and avoid over-exposure. The difference is small, but if you had to find one, that would be it.

Low-light photography

Galaxy S9+

In low-light, the Mi Mix 3 performs very well too, again competing with the Galaxy S9+ very well. Here again, there are differences in philosophy with Samsung favoring noise removal at the expense of sharpness, while Xiaomi is prioritizing sharpness, even if it means having a slightly noisier image.

In this round, I’d give the Galaxy S9+ a slight win, because it preserves the colors better (if you know what the scene really looks like), which is one of the most challenging things to do in low-light. The Sony XPERIA XZ2 and the Pixel 3 are other phones that do this well. Overall, the Mi Mix 3 performs nearly as well as the S9+ in low light, despite a massive difference in price.

comparison image Acomparison image A

Night Mode: if you don’t mind more image processing, The Xiaomi Mi Mix 3 has a dedicated Night Mode, or ultra-long exposure mode, during which it will take several dozens of photos at different exposures, and merge them back into a single image.

The result is a boosted HDR-style photo that might look supernaturally bright (as in night turning into day). Some people just love it; others don’t – it’s up to you. Because it’s bordering on being a filter, we don’t review the same way as traditional low-light photography, but you should be aware of it.

This night mode competes directly with Huawei’s P20 Pro and Mate 20 Pro Night Mode, which introduced this to the world in March. Eventually, we think that other OEMs will include a similar night mode, because it is a very compelling feature.

Ultra-long exposure Night Mode

Selfie Camera

In Asia, selfies can be a huge deal, so you often find more powerful selfie cameras than US flagship phones, including the recent Galaxy S and iPhone phones. The Google Pixel is trying to change that a bit, though. We found the selfie camera to be very good, and we’ll compare it with leading phones when the final unit is available.

The 24 Megapixel Selfie camera is powered by the Sony IMX576 Exmor RS sensor, which is capable of pixel-binning to quadruple the sensor pixel surface during night shots, going from 0.9µm/24MP to 1.8µm/6MP). Pixel binning is a way to reduce noise in a low-light situation while having higher details in bright light conditions.

The camera includes a selfie LED flash, an accessory often sacrificed because there is so little space on a regular phone. Thanks to the sliding mechanism, Mi Mix 3 can offer this option to its users.

Camera system technical analysis

In the Mi Mix 3, the primary rear camera aperture of f/1.8 is good, and the sensor size of nearly 24 mm2 would be considered large (for a smartphone).

The 12 Megapixel resolution of the Sony IMX363 sensor could be a useful metric for photographic detail and sharpness on a sunny day. Landscape photos with a higher megapixel count could lead to finer details. Between 12 MP, 16 MP and 21 MP differences in small details can be quite noticeable, if printed or viewed on a large and/or high-PPI display.

In dark scenes situations, the high Megapixel count (>12) has little influence. Also, the physical size of each sensor pixel is critical. The 1.4μm pixel size of this sensor is very good, and frequently seen in high-end phones, but there are even bigger pixels!

With higher megapixel counts, sensing pixels (sensels) may have to be smaller. Each obtains less light information, and in low-light scenes, it is better for the overall photo quality to sense more light with fewer (but bigger) sensels than the opposite. It is a balance that needs to be found. Today, 12 Megapixel seem to be the best sensor trade-off between sharpness, low-light and autofocus performance.

The availability of an Optical Image Stabilization (OIS) module on the primary camera augments the potential for taking sharp images in daylight, and brighter images in low-light situations

OIS helps to achieve better image clarity and higher low-light performance by offsetting tiny hand-shaking motion. OIS makes it possible to leave the shutter open longer to capture more light (more extended exposure). Optical and digital stabilization are completely different, with digital stabilization suitable to help video recording smoothness.

EIS (Electronic Image Stabilization) is not available on this handset. Because of this, the video recordings may be shakier than competitors that have this feature. The autofocus of the Mi Mix 3 camera is based on Dual Pixel Phase Detection technology, which is extremely powerful.

Dual-Pixel AF sensing is a remarkable kind of Phase Detection hardware. It has all the Phase-Detect advantages in terms of performance and efficiency but has better AF sampling points. This is works by splitting sensing pixel (sensels) into two small sub-pixels.

By comparing what they “see” from a slightly different point of view, it is possible to know if the image at that pixel is focused (in-phase) or not (out of phase). You can read our detailed Dual-Pixel AF article if you want to know more. Dual-Pixel AF is currently the best and fastest way to perform autofocus on phones. It was initially deployed on specific high-end DSLR cameras.

960 FPS Slow-Motion (with frame interpolation)

Xiaomi has included a 960 FPS video recording capability in the Mi Mix 3. It works pretty well, but after looking at the videos, I spotted frame interpolation. After checking, Xiaomi has confirmed that the 960 FPS is obtained from frame interpolation, a technique used by Huawei in its P20 Pro phone as well.

Frame interpolation won’t look as good as a real 960 FPS capture because 75% of the frames are generated with a linear motion. Details may also be lost or blurred out if they are small enough. However, in many cases, the result is very decent and worth sharing. This video shows the difference between true 960FPS and interpolated 960FPS:

HDTVs are using the same kind of techniques to go from 60 to 240 HZ, so it’s a proven technology. In this case, it’s probably turning a 240/480 FPS video into 960FPS (interpolated). Looking at the hardware, the Sony IMX363 of the primary camera does not have the capability to record at 960 FPS, to begin with, so it all makes sense.

2X Optical Zoom

Xiaomi’s Mi Mix 3 has a secondary 2X optical zoom camera module that also serves as a Camera Depth Sensor for Bokeh. 2X zoom does help a bit with image quality, and there’s support for electronic image stabilization (EIS) when shooting videos in this mode.

The Huawei P20 Pro and Huawei Mate 20 Pro have even higher zoom cameras with 3X optical zoom. They typically work best during the daytime, because they use relatively small sensors. At night, the main (non-zoom) camera can be a fallback.

Battery

The battery capacity of Mi Mix 3 is 3200 mAh, which is very good overall, but rather standard in its own category. It can be charged with the Qualcomm Quick Charge 4+ standard (18W), but the included charger is Quick Charge 3.0 (18W).

Battery life is one of the most sought-after features of a smartphone. A key indicator is, of course, the battery capacity — especially within the same ecosystem (Android, iOS or other). Battery life can be affected by a lot of factors, but the main ones are the processor aka SoC, display and wireless radios (LTE broadband, WiFi, the cell towers location and more). It is impossible to accurately pinpoint through synthetic tests how much energy drain YOUR unique needs will induce. However, two things are without a doubt always good:

  • A higher battery capacity
  • Rapid charging

It is generally not possible to predict realistic battery life by running synthetic tests. Things such as display brightness, (LTE/WiFi) radio usage and distance to access points will change too much. Also, the number of apps on-board and their usage cannot be estimated. Battery capacity is the most critical battery-life indicator for YOUR usage.

Wireless charging can be very agreeable, and the Mi Mix 3 comes with an integrated wireless charging option (wireless charger in the box!).

Since this product has a very large display, keep in mind that larger screens tend to require more energy due to the more significant surface area to illuminate. It depends on the brightness, but the potential for higher energy exists, so a larger battery capacity is preferable.

This handset has a relatively common screen resolution. Although this may be just enough from a display quality point of view, having fewer pixels to manage is a bit better for battery life.

System Performance

This handset central processor is a Qualcomm Snapdragon 845 (8 Cores, 2.8 GHz) which has access to 6, 8 or 10 GB of memory (RAM) depending on the model you pick. Note that the 10 GB RAM is only available in the special edition. If you have been shopping around, you will notice that virtually all high-end Android phones, minus Huawei’s, use that particular chipset.

The amount of RAM is paramount for heavy users, or for having many apps/services on the device. When the memory is tight, the phone may become less responsive if the system has to read/write from the slower Flash storage instead. This has been one of the differentiators between low and high tiers of phones, but this line is blurry now.

We are still waiting on the retail unit to run final benchmarks, but nearly all the Snapdragon 845 phones land into a well-defined performance zone, and we expect this one to perform comparably. That’s precisely what our current numbers show.

Benchmarks alone should NOT drive a smartphone purchase decision. To learn more, read our Are Benchmarks Important? Article.

Wireless Broadband Performance

The Mi Mix 3 has a CAT12 (600 Mbps ) LTE modem. This level of performance is quite good in absolute terms, but shy from what other Snapdragon 845 handsets can do: CAT18/1200 Mbps. Huawei has a 1400 Mbps modem that was just introduced to the market. That said, don’t panic, carriers have not always rolled out full support for the latest speeds. Perhaps check with your carrier to see if this is a big deal for you, or not.

Xiaomi has talked about a 5G version of this handset, but it won’t show up before 2019, so we will have to update this article when we know more about what kind of 5G technologies Xiaomi intends to integrate.

Wireless networks (3G/4G) performance is often thought as peak download/upload speeds, but it is the average speed that counts. These days 4G/LTE is the primary network of interest, but 5G is coming. The higher the theoretical LTE performance and the better the average actual experience. Also, wireless providers have better and more efficient LTE networks to diminish their own costs.

Value: where the real Xiaomi power is

It’s impossible to review a Xiaomi phone without measuring the value-proposition it brings. That is the whole concept of Xiaomi: provide high-end hardware at unbeatable prices, then make money on web services.

We’ve already established that for traditional photography in both bright and low-light, the Mi Mix 3 performs up there alongside the best mobile cameras — for about half the cost of well-known high-end phones.

When it comes to processor performance, something similar is happening, and you can clearly see that Xiaomi brings tremendous value when looking at nearly every aspect of the product. The Mi Mix 3 has a 75% better value than the best known high-end phones, and it even manages to beat OnePlus, which is itself a value-optimized brand.

For performance-minded customers, Xiaomi has even introduced the Pocofone brand, and the new Pocofone F1 crushes everyone at this processor-value contest. We’re working on that review right now, so recheck Ubergizmo.

Conclusion

The Xiaomi Mi Mix 3 sets itself apart with its full-screen design, which targets a particular market of users who love having all the screen they can get – today. Because the design decisions behind this product are bold and therefore risky, the phone itself might be polarizing. Some people will love it, while others may laugh at the slider idea. In the end, it only matters how many people love it, and so far, the feedback is seemingly excellent.

"AN AWE-INSPIRING VALUE IN A BEAUTIFUL CERAMIC CHASSIS"

Design aside, the system and camera performance are excellent, and if you take value into account: it’s an awe-inspiring value in a beautiful ceramic chassis for a phone that starts at $475.

Perhaps the final thing to ponder about is the MIUI user interface which is Xiaomi’s layer on top of Android. Like any other interfaces, it may take a few days to get used to it, and depending on your habits, you may like it (or not), but we recommend watching a video or two to have a better idea.

We will update this article when we receive the retail unit of the phone with the global firmware. Keep in touch with us via FB, Insta or YouTube, to be notified.

Filed in Cellphones >Reviews. Read more about Android, Xiaomi.

6.39"
  • 2340x1080
  • AMOLED
  • 403 PPI
12 MP
  • f/1.8 Aperture
  • OIS
3200 mAh
  • Non-Removable
  • Wireless Charging
6-10GB RAM
  • Snapdragon 845
Price
~$475 - Amazon
Weight
218 g
Launched in
2018-10-01
Storage (GB)
  • 128
  • 256
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