Xiaomi Mi 4 review: Dragons forever

Display

The Xiaomi Mi 4 features a similar 5" Full HD IPS display to the one we saw on the Mi 3. It has a pixel density of 441ppi, which places it among the best. This time around, the glass covering the display lacks any protection and it might be a good idea to apply a screen protector.

The 5" IPS display Xiaomi Mi 4

Taking a closer look at it under our digital microscope reveals a standard RGB arrangement of the sub-pixels that make up the Xiaomi Mi 4 LCD panel, much like on the Mi 3.

The display on the Xiaomi Mi 4 has a higher maximum brightness level compared to the one on Xiaomi Mi 3, while retaining the same good contrast and colors. Also compared to the Mi 3, the Mi 4 screen backlight is much more uniform and you can't easily tell the main source of backlight as you could on the Mi 3.

Subjectively, the Mi 4's display tends to produce cooler images, while the colors on the Mi 3 are warmer. Xiaomi is providing options for color temperature and saturation, so you can tweak the display to your liking.

The sunlight legibility has been improved as well and the Xiaomi Mi 4's display performs admirably outdoors and you will be able to see what's happening on the screen even on the brightest day.

Sunlight contrast ratio

• Sony Xperia E
  1.215
• Xiaomi Mi 4
  2.424
• Samsung I9000 Galaxy S
  3.155
• Samsung Galaxy S5 mini
  3.174
• Nokia N9
  3.069
• Samsung Galaxy Alpha
  3.509
• Samsung Galaxy Note
  2.97
• Samsung Omnia W
  3.301
• Samsung Galaxy K zoom
  3.675
• HTC One S
  2.901
• Gionee Elife S5.5
  3.386
• Alcatel Idol X+
  3.527
• Samsung Galaxy S5
  3.549
• Samsung Galaxy Note 3 Neo
  3.487
• Motorola Moto G
  2.477
• BlackBerry Z30
  2.79
• Samsung I9300 Galaxy S III
  3.419
• HTC One Max
  2.537
• Samsung Galaxy Note 3
  3.997
• Apple iPhone 5s
  3.565
• Apple iPhone 5c
  3.512
• Sony Xperia Z1
  2.95
• Nokia 808 PureView
  4.698
• Huawei Ascend P1
  2.655
• Sony Xperia ZR
  2.672
• Samsung Galaxy S4 zoom
  3.118
• Nokia Lumia 900
  2.562
• BlackBerry Q10
  2.856
• Samsung I9190 Galaxy S4 mini
  3.127
• Nokia Lumia 925
  3.402
• Samsung I9100 Galaxy S II
  2.832
• Samsung I9505 Galaxy S4
  3.352
• Nokia Lumia 720
  2.512
• HTC One
  2.504
• Samsung I8730 Galaxy Express
  2.861
• Sony Xperia Z
  2.462
• Samsung Galaxy S II Plus
  2.801
• Motorola RAZR MAXX
  3.42
• Samsung Galaxy Premier
  2.958
• Samsung Ativ S
  3.129
• Apple iPhone 5
  3.997
• Huawei Ascend P6
  1.865
• Nokia Asha 311
  2.25
• Apple iPhone 4S
  2.269
• Oppo Find 7a
  2.279
• HTC One (M8)
  2.371
• Motorola RAZR i
  2.366
• Samsung Galaxy S III mini
  2.422
• Alcatel One Touch Hero
  2.272
• LG G Flex
  2.407
• HTC Desire 600 dual sim
  2.262
• Sony Xperia ZL
  2.352
• Samsung Galaxy Note II
  2.307
• Sony Xperia Z Ultra
  1.578
• Apple iPhone 4
  2.016
• HTC One (E8)
  2.185
• Nokia Lumia 820
  2.193
• HTC One X
  2.158
• Nokia Lumia 630
  2.056
• Nokia Lumia 920
  2.17
• Sony Xperia acro S
  2.119
• Sony Xperia SL
  2.078
• Nokia N8
  2.144
• Nokia 515
  2.134
• LG Nexus 5
  2.228
• HTC Desire 500
  2.129
• Nokia Lumia 1020
  2.103
• Oppo Find 5
  2.088
• Samsung I9295 Galaxy S4 Active
  2.022
• BlackBerry Z10
  2.051
• Nokia Lumia 620
  2.142
• Meizu MX3
  1.754
• HTC Windows Phone 8X
  1.873
• Xiaomi Mi 3
  2.001
• Sony Xperia T
  1.894
• Sony Xperia J
  1.932
• HTC One mini 2
  1.94
• Acer CloudMobile S500
  1.931
• Sony Xperia Z2
  1.944
• Huawei Ascend P7
  1.992
• LG Nexus 4
  1.926
• LG G Pro 2
  1.922
• Nokia Lumia 1320
  1.941
• Nokia Asha 308
  1.911
• Samsung Galaxy Camera
  1.938
• Samsung Galaxy Mega 6.3
  1.913
• Sony Ericsson Xperia ray
  1.955
• HTC Butterfly
  1.873
• LG G2
  1.976
• HTC Desire X
  1.878
• Oppo R819
  1.957
• HTC One mini
  2.003
• Sony Xperia SP
  1.733
• Samsung Galaxy Mega 5.8
  1.35
• Huawei Ascend Mate
  1.845
• LG Optimus 3D
  1.542
• Samsung Galaxy S Duos
  1.4
• BlackBerry Q5
  1.682
• Samsung Galaxy Xcover 2
  1.632
• HTC Desire 616 dual sim
  1.797
• LG Optimus GJ
  1.666
• BlackBerry Curve 9320
  1.488
• Oppo Find 7
  1.691
• Sony Xperia L
  1.351
• HTC Butterfly S
  1.867
• Samsung Galaxy Core
  1.563
• Sony Xperia M
  1.473
• LG Optimus Vu
  1.68
• Motorola Moto E
  1.545
• Nokia Lumia 610
  1.432
• Nokia Lumia 625
  1.371
• Sony Xperia U
  1.758
• LG G3
  1.82
• Sony Xperia V
  1.792
• Sony Xperia M2
  1.393
• LG Optimus 3D Max
  1.658
• LG Optimus G Pro
  1.552
• Samsung Galaxy Ace 2 I8160
  1.566
• HTC Desire 816
  1.783
• Samsung Galaxy Ace 3
  1.622
• Sony Xperia go
  1.577
• Oppo N1
  1.47
• Sony Xperia T2 Ultra
  1.74
• HTC One V
  1.685
• LG G2 mini
  1.838
• Nokia Lumia 1520
  1.813
• Jolla Jolla
  1.605
• LG Optimus 4X HD
  1.691
• Sony Xperia E1
  1.372
• Sony Xperia Z1 Compact
  1.772
• Gigabyte GSmart G1355
  1.361
• LG Optimus G
  1.753
• HTC Desire 700 dual sim
  1.769
• Samsung Galaxy Grand Neo
  1.393
• Meizu MX 4-core
  1.462
• Samsung Galaxy Grand 2
  1.38
• HTC Desire V
  1.646
• Nokia Asha 302
  1.537
• LG Optimus L7
  1.269
• Nokia X
  1.291
• Sony Xperia miro
  1.324
• Samsung I9082 Galaxy Grand
  1.321
• HTC Desire C
  1.3
• Samsung I8530 Galaxy Beam
  1.315
• LG Optimus L9
  1.227
• Sony Xperia neo L
  1.169
• Nokia Lumia 510
  1.268
• Samsung Galaxy Fame
  1.245
• Nokia Asha 305
  1.178
• Samsung Galaxy Young
  1.22
• Nokia Asha 503
  1.281
• Samsung Galaxy Pocket
  1.18
• Nokia XL
  1.204
• Sony Xperia C
  1.283
• Nokia Asha 306
  1.175
• Meizu MX
  1.221
• Nokia Asha 501
  1.27
• Sony Xperia E dual
  1.203
• Sony Xperia tipo
  1.166
• Nokia Lumia 520
  1.161
• Samsung S6802 Galaxy Ace Duos
  1.148
• Samsung Galaxy mini 2
  1.114

The high-sensitivity mode for Glove use is available here much like on the Mi 3, but you probably shouldn't leave that turned on if you don't need it, because it may drain your battery faster.

Finally, there is a way to prevent accidental screen unlocks, while the phone is in your pocket. If enabled, you won't be able to unlock the screen while something is covering the proximity sensor. Again, that would probably take its toll on the battery life.

Controls

The Xiaomi Mi 4's controls are pretty much the same as what we found on its Mi 3 predecessor. Almost the entire front is occupied by the 5" display, but its bezels have gotten a lot thinner. Above the screen we find the earpiece, with a couple of sensors and the 8MP selfie camera around.

The 5" display • looking above and below the screen

Xiaomi once again has decided to keep the capacitive controls instead of wasting precious screen real estate. The trio yet again uses the older arrangement with Menu, Home and Back keys.

The microSIM slot is alone on the right and you will need a SIM ejector to pop it out. The right side of the Xiaomi Mi 4 has the metal volume rocker and power/lock key.

The microSIM slot on the left • the volume rocker and the power/lock key on the right

As usual, the 3.5mm audio jack is on the top and an IR blaster keeps it company. You have a choice of apps that you can install to make use of the Infrared port for controlling various home appliances such as TVs, media players, air conditioners, etc.

The bottom of the Mi 4 has the microUSB port and a rather big grille hiding the primary microphone and the loudspeaker.

A peek at the top and bottom of the Xiaomi Mi 4

The Xiaomi Mi 4's rear features the 13MP camera lens with F1.8 aperture, which uses the latest generation of Sony sensors. There is a single-LED flash beside it.

The 13MP Sony camera is on the back

The 3,080 mAh battery hides beneath the plastic rear cover. To get to it you need a small suction cup to pull the cover open. The battery beneath it however is not user-replaceable. It's glued to the the phone and we didn't dare put a pressure on removing it in our review unit.

There is no microSD card slot on the Xiaomi Mi 4 either.

Battery life test

Xiaomi has put a 3,080mAh battery inside the Mi 4, a solid enough unit for a 5" device. We ran our battery test and the Xiaomi Mi 4 scored a 68h rating, which means you can count on the battery to last just short of 3 days if you do an hour each of calling, browsing the web and video playback a day.

The Xiaomi Mi 3 was almost there too with a rating of 66h.

Perhaps this is the right place to mention that we didn't like how hot the Xiaomi Mi 4 became with the charger plugged in.

For a more detailed breakdown of the Xiaomi Mi 4 battery performance check out our blogpost.

Our proprietary score also includes a standby battery draw test, which is not featured in our battery test scorecard but is calculated in the total endurance rating.

Our battery testing procedure is described in detail in case you want to learn more about it.

Connectivity

The Xiaomi Mi 4 runs on the capable Snapdragon 801 chipset which is LTE-enabled, unlike the one on the Mi 3. The Mi 4 also offers quad-band GSM connectivity and quad-band 3G connectivity with HSPA support.

The rest of the connectivity features include dual-band Wi-Fi a/b/g/n/ac support and Wi-Fi Direct. There is also support for Bluetooth 4.0, GPS and GLONASS, plus an FM radio.

The IR blaster is located on the top and coupled with the right software, you can use it to operate pretty much any IR remotely controlled home appliance, turning the Xiaomi Mi 4 into a universal remote.

Unlike the Mi 3, there is no NFC connectivity on the Mi 4. It seems the company thinks there are too few users actually using the feature.

A microUSB 2.0 port handles charging and data connections. Media transfer mode is supported for accessing the phone's built-in memory and microSD card over a USB connection.

The microUSB port also supports USB On-the-go for connecting USB peripherals such as pen drives, keyboards or real USB hard drives.

Wireless screen mirroring is available via the Miracast protocol.