Xiaomi Redmi Note 4 16GB Review

Xiaomi Redmi Note 3 Pro and Redmi Note 3 are probably some of the best-selling Xiaomi devices ever. The fact that recently the manufacturer has celebrated selling 110 million units of Redmi devices for the past three years speaks for itself. Indeed, this company is one of the best in the smartphone market in terms of providing real value for money. Its latest device from the Redmi Note series - the Redmi Note 4 - is already available on the market with a price that is already low - CNY 899. Obviously, the new model is under the pressure of providing a noticeable upgrade over the previous generation, while aiming to retain that affordable price, so lets get deeper into it and check whether it meets up expectations. Parallels with the Xiaomi Redmi Pro are inevitable, so bear with us.

Specifications

Xiaomi Redmi Note 4 is equipped with a 5.5-inch IPS display with a resolution of 1080 x 1920 pixels and a pixel density of 401 ppi. Its static contrast ratio and peak brightness level are typical for a good LCD display and measure 1000:1 and 450 cd/sq.m. Furthermore, NTSC coverage is 72%, which means it is very close to the full sRGB coverage and promises lack of over-saturation and color deviation. 2.5D curved glass as a top display year has become the norm and this model is no exception. Hardware-wise, the smartphone is based on the 20nm MediaTek Helio X20 MT6797 chipset, which features the so called three-cluster architecture, created to optimize both performance and power efficiency. The first cluster consists of two Cortex-A72 CPU cores clocked at 2.1GHz, the second - of four Cortex-A53 CPU cores clocked at 2GHz and the third features another quadruplet of Cortex-A53 cores clocked at 1.4GHz. A 700 MHz quad-core Mali-T880 MP4 GPU is responsible for the graphics. There are two variants of the model in terms of RAM and storage. The first is equipped with 2GB of RAM and 16GB of internal memory. The second has 3GB of RAM and 64GB of internal memory. In both cases, storage can be expanded with up to 128GB. The options for connectivity include dual-band Wi-Fi 802.11 a/b/g/n/ac, Wi-Fi Hotspot, Wi-Fi Direct, Wi-Fi Display, Bluetooth 4.2, USB Type-C 2.0, USB OTG and as long as it concerns satellite navigation, the device works with the three main systems - GPS, Glonass, BeiDou. Regarding network bands, these include 2G GSM (850, 900, 1800, 1900 MHz), 2.5G CDMA 800 MHz, 3G W-CDMA (850, 900, 1900, 2100 MHz), 3G TD-SCDMA (1880-1920, 2010-2025 MHz), 4G FDD-LTE (900, 1800, 2100, 2600 MHz), 4G TDD-LTE (1900, 2300, 2500, 2600 MHz). Both SIM cards support 4G LTE Cat. 6 with VoLTE. There's a fingerprint sensor on the rear below the main camera along with a proximity, light, accelerometer, compass, gyroscope, and Hall sensor. The primary camera is equipped with a 13-megapixel Samsung S5K3L8 ISOCELL sensor with optical format 1/3.06", a 5-element lens with an f/2.0 aperture, PDAF and a dual-tone LED flash. The front-facing camera features a 5-megapixel Samsung S5K5E8YXB6 sensor with an optical format 1/5" and an f/2.0 lens. Power is supplied by a 4100 mAh Lithium-Polymer battery with an ultra high-density (713 Wh/L). It is non removable and arrives with a 5V/2A fast charger. For complete details, here is the full list of Xiaomi Redmi Note 4 16GB specifications.

What's in the box

Redmi Note 4 is the fifth Xiaomi device we review and its packaging is typical for the manufacturer. The box is the same rectangular white one, with the MI logo on top, photo of the model and its name below the image. Of course, some basic specifications, supported networks and official certifications are printed on the back of the box. Once you open the lid you get access to the device placed in the top level compartment. Below it, there are a USB cable and a two-pin wall charger (US NEMA-1 plug standard) along with the SIM tray pin, user manual and warranty card. In order to be able to use the US-standard charger, you will need a plug adapter, if you live outside the US, Canada and some Latin American countries.

Design, build and controls

Xiaomi Redmi Note 4's body is made of a high-quality aluminum ingot that has undergone more than 30 processes in order to achieve a more unified metal structure. Its back has a matte finish that is not slippery. Along the vertical edges the back is slightly curved in order to provide comfortable grip on one hand, and on the other - to visually decrease the thickness of the device. The latter is also due to the fact that both, rear and front edges are chamfered and glossy, making the matte frame between them look really thin. In addition, the front plastic housing of the display protrudes above the frame and is filled in with the 2.5D curved glass. Yes, filled in is the right verb here, because the glass does not reach the frame, but this white plastic housing, which serves as a frame for the display. It is the same with the Redmi Pro, which however has a brushed metal effect on its back. At a first glance, both models seem to be visually identical, however, there are some minor differences, besides the back design effect. For starters, Redmi Note 4 is heavier with 1 gram, narrower with 0.2 mm, shorter with 0.5 mm and thicker with 0.2 mm. However, according to its dimensions and weight the model is quite average for a 5.5-inch smartphone with a 4100 mAh battery. More specifically, the device weighs 175 grams and is 76 mm wide, while its thickness measures 8.35 mm. The only relatively more compact dimension of the Redmi Note 4 is its height - 151 mm. It arrives in three colors. The one we are reviewing - silver with a white front, as well as gold with a white front and grey with a black front. The layout of the controls differs from that of Redmi Pro, especially in the upper part of the device. The top frame includes a 3.5 mm jack, a centrally positioned infrared port, and a mic (from left to right). The Pro has the same, but the mic and jack are on the left and the infrared port is on the right. The bottom frame of the Redmi Note 4 includes holes for a mic, a USB 2.0 port and another set of holes for the speaker. The same is with the Pro, but it has a USB Type-C 2.0 port, instead. The left and right frames are identical in the two models, the left housing the dual SIM tray (hybrid) and the right - the volume rocker and the power button below it. The places of the modules above the Note 4 display on the front of the smartphone are switched compared to those of the Pro - proximity sensor, earpiece, front camera and LED notification light (from left to right). In the Pro the LED light is to the opposite left side. The navigation bar is also different, because the Redmi Pro has a high-quality ceramic home button with an embedded fingerprint sensor and only the menu and back buttons are capacitive backlit dots. In Redmi Note 4, all three buttons are backlit, capacitive ones. Their behaviour can be managed from Settings>Additional settings>Buttons. The layout on the back is different as well, because instead of having two cameras, the Redmi Note 4 has a primary camera module, a horizontal, dual-tone LED flash and a fingerprint sensor, all three vertically centered. Of course, the MI logo is at the bottom, above the lower antenna band. The build is definitely solid, and, actually, with all Xiaomi devices we have reviewed, this has never been an issue and in terms of build, this is a reliable brand.

Display

Xiaomi Redmi Note 4 features a 5.5-inch IPS display with an FHD resolution (1080 x 1920). Borders and bezels are thick, but this is expected, so no surprises here. The display unit has a 2.5D curved top glass layer, but as usual for budget smartphones, there's no mention of a special protective glass. Neither the Mi Max, nor the Redmi Pro have such. According to the specifications, the display panel has a 1000:1 contrast ratio and a peak brightness of 450 cd/m², while covering 72% of the NTSC color space. Our subjective view about our unit is that it has one of the best LCD displays on smartphones we have reviewed. The measurements below do prove that the display unit on Redmi Note 4 is a quality one and this is a big plus having in mind the really low price of the model. The peak brightness of our review unit is 381.816 cd/sq.m., which is below the specified 450 cd/sq.m. More interestingly, the black luminance values are way better than those of other smartphones with IPS displays we have tested. Another good feature is that the contrast ratio is very consistent at all brightness values and is higher than specified: 1300:1 Only at 0% brightness it is 1008:1, where the white luminance is 5.425 cd/sq.m. and the black luminance is 0.005 cd/sq.m. Finally, the color temperature is also very good for a smartphone display and very consistent, too - within the 7200-7300K range.

Brightness	White luminance	Black luminance	Contrast	Color temperature
100 %	381.816 cd/m2	0.293 cd/m2	1303	7342 K
75 %	264.235 cd/m2	0.209 cd/m2	1302	7270 K
50 %	154.025 cd/m2	0.119 cd/m2	1294	7341 K
25 %	64.045 cd/m2	0.049 cd/m2	1307	7205 K
0 %	5.425 cd/m2	0.005 cd/m2	1085	7316 K

The display has a standard striped pixel geometry. Its 72% coverage of the NTSC color space means that it should be very close to covering the whole sRGB color gamut. Indeed, it is very close to that with slight deviations in all color components - red, green, and blue. You can tweak the color saturation and temperature from Settings>Display. This section also contains a Reading mode, which warms up the display color and background, so it is more comfortable reading in low light conditions or at night. The viewing angles are excellent in terms of preserving color, but the horizontal ones show some loss in light. The vertical ones do not have this problem.

OS, UI and software

Xiaomi Redmi Note 4 arrived with an original MIUI 8, which immediately received an update to v8.0.9.0.MBFCNDG, which provides some minor optimizations and fixes. This is the Chinese version of MIUI as there isn't an official international one yet. As usual, it is deeply customized and its 8th version goes much closer to creating a unified Xiaomi media eco-system, than the MIUI 7. The lock screen is quite "clean" with an option to swipe up in order to unlock and a shortcut to the camera app. The Wallpaper Carousel is gone and from the Settings you can choose shortcuts to which apps should appear on the lock screen. The home screen contains a row of docked apps: Dialer, Messenger, Browser and Camera. Pre-installed and additionally installed apps appear on successive screens. To access the list of active apps, you have to tap the menu button. You can remove them from the list by swiping them up one by one, or use the Clean All function. A swipe down gives you access to a shortcut for locking the app and preventing it from being cleaned from the list and another shortcut is to more info about this app. A new feature of MIUI 8 is the way you preview apps in this list. They can either be shown as smaller screens (such as it is up to now), or as icons. The Volume shade is also different, compared to MIUI 7 and is no longer circular, but a rectangular one with all three volume types together. It is a traditional MIUI feature that if you zoom in with two fingers on the home screen, it opens the Widgets menu. You can also access it if you tap and hold the menu button. It provides the same options as in the older UI version: moving apps and folders from one screen to another with the possibility to move more than one app at once; a very distinctive list of widgets to place on one of your screens, including toggles, shortcut to settings, etc.; a choice of wallpapers; and a choice of a screen transition effect. There's an icon to the right of the clock widget on the home screen and if you tap it you get access to various clock styles, from which you can choose. The Notifications and Quick Settings shade has undergone a more significant redesign. By default, in MIUI 8 both are merged into one with the shade containing a search function, information about the weather, a settings icon, horizontal list of toggles, which you have to swipe to the left and right, the brightness level bar and the notifications listed below all this. From the settings, you can choose to separate them, though. Thus, by swiping from the top of the screen you open the Notifications shade and after swiping to the left you access the list with toggles. A long press on the home and back buttons does nothing, unless you choose otherwise from the Additional settings>Buttons menu. The Power off menu is the same old MIUI one. The Settings menu of MIUI 8 does look different in terms of being less colorful and re-structured, compared to MIUI 7. For starters, there's a search bar above the list with Settings. With it you can search the whole menu and discover options, which are otherwise deep inside it. As usual, the first group of settings is the Network one. It lets you manage your SIM cards, calls, wireless connections, including VoLTE on/off, Wi-Fi Direct, Wi-Fi Display, Bluetooth, Wi-Fi Hotspot, etc. The Personal group of settings comes second and in MIUI it is called Device. Display is the first sub-group of options and besides all standard features, it lets you activate and manage a Reading mode as well as tweak color saturation and temperature. The Wallpaper and Theme settings are second and third, providing access to both offline and online sources. This almost entirely duplicates the function of the Themes app, but more on it later. In MIUI 8 you get a toggle for Silent Mode in the Sound & vibration sub-group, which is fourth. It also provides direct access to the various volume types (three instead of five) and there are the Audio settings, which include setting up your earphones - the same feature can be accessed from the Music app, too, as well as from Additional settings>Headphones & audio effects. The Lock screen & password is the first sub-group in the third main group of settings, called System and device. It is not extensive as the Security menu in stock Android 6.0 Marshmallow. You can setup up to five fingerprint IDs, choose a type of lock password, choose what type of shortcuts should appear on the lock screen, smartcover options, and a toggle for Child mode. The second subgroup is the Notifications & status bar, which contains an option, whether the Notifications shade and the Quick Settings one should be merged or not. Of course, you can also manage which apps should produce notifications, re-arrange the toggles in the Quick Settings as well as change the appearance of the status bar. The third sub-group of options and the most noteworthy software change in MIUI 8 is the Second Space feature. When you switch it on, the phone creates a second virtual device within the smartphone. It has all the functions of a normal device - its own home screen, apps, and so on. When this feature is on, a Switch icon appears on both home screens, so you can switch in-between without hustle. The second space also receives a Manage space and a Move data icon, because you can move files and contacts from the first to the second one and use the second one with different passwords, for example. Following is the DND mode sub-group with scheduling options. The Battery & performance sub-group will be discussed in the Battery section of this review, while the Storage monitor doesn't need explanation and is followed by the Lite Mode functions, which needs to reboot after activating it. It changes the UI to a more accessible one by people who are visually impaired or are in a situation where they need precise and quick access to main functions, that's why the UI's icons are huge, so are the fonts and the whole interface is extremely simplified. The Additional settings is the last sub-group of options and is very extensive. It starts off with Date & time and Language & input, which are self-explanatory and goes on with the Privacy and Child mode settings. Unlike MIUI 7, the eighth version contains a Quick Ball functions. This is a floating dot, which is just another navigation tool as it provides shortcuts to a back function, home screen, device lock, screenshot, and list with running apps. You can change these shortcuts in order to adjust the Quick Ball function to your personal preferences. The rest of the options include the usual management options of the LED notification light, navigation bar Buttons, Headphones and audio effects, One-handed mode, Accessibility, Backup & rest and the Mi Mover. The fourth main settings group is the Accounts one. It manages the MI Account, any other accounts you'd have and the synchronization between them. The fifth and last group is App Settings, from where you can check the system and installed apps with their settings, activate the dual app function for using one and the same app separately, manage app permissions and lock (the same as in the Security app). As usual, the last menu is About phone, which also includes the System updates feature that doubles the function of the Updater app. All apps on the device appear on successive screens, which can be swiped back and fourth. Pre-installed apps are not an overwhelming in number, a large portion of them is placed in the Tools folder. You can uninstall an app by holding on its icon and moving it to the Trash icon that appears. A dialogue requiring confirmation appears, so there's no risk of removing an app by mistake. The main app is the Dialer, which is actually merged with the contacts and the separate icons for the two just lead to the corresponding tabs. The app has a third tab as well for Yellow Pages. The Messenger is pretty simple and straightforward. The Browser is very quick and offers a built-in ad blocker, night mode for more comfortable reading (background turns black and the font is white). The Calculator is extended and features not only classic and scientific calculation options, but also conversions of currency rates, mass, volume, etc. The Clock app is already familiar with four different tabs for alarm, clock, stopwatch and timer functions. The Calculator is enriched with features and provides not only classic and scientific options, but also currency and measurement converters, tax and mortgage calculations, and so on. The default browser is improved and offers data saving mode, night (reading) mode, built-in ad-blocker, supports Find on Page, and scrolling by using the volume button. The Barcode reader does not only this, but also outputs business cards and documents with the scanned data. The Explorer is an extensive app with three tabs. The Categories is the home screen with access to all types of files grouped in corresponding folders. There's a Recents tab and a Storage one as well. Furthermore, with MIUI 8 Xiaomi offers a Virtual SIM app, which allows you to use mobile services via Xiaomi without swapping SIM cards. The More apps folder contains a Cleaner app in Chinese and there's a row of suggested apps from the App Store. There's a classic Sound recorder as well as a Voice search app, which can also output voice to text. Fans of games may try the Games app, which, however is in Chinese and provides content only in this language. Most probably, this app and all others similar to it will not be available in a future international version of MIUI 8 of the Redmi Note 4. The Radio is no different from previous MIUI versions. Similar to all other apps with rich media content, the Xiaomi Video player provides a home screen with access to both online and offline content. Besides watching videos and movies, you can also stream them. The Security app provides various tools for monitoring and optimizing your smartphone. There's a Cleaner, which shuts all unnecessary processes to free more space and provides suggestions for further optimization. There's a Data usage tab for monitoring and managing the way your device uses mobile data with options to top it up (only for Xiaomi mobile data services). The Blocklist is where you should put contacts you wish to block, including calls and messages. There's a Virus scan as well as a Permission tab to manage your app permissions, including locks. The Security tab also provides a Battery usage function, but this will be described in more detail in the Battery section of this review. The Themes app is worth looking at, because, though familiar, it offers more customization than expected. You start off with the home screen and don't be scared that it is in Chinese. It lists the newest and hottest available themes for download. Then you get access to two types of theme grouping. The last two tabs provide you with access to the themes available offline on your device, the app settings and the Customize theme option. It lets you make a mix of available home screen styles, dial pad and messenger styles, etc. The second major tab in the Themes app is the Wallpapers one, again with access to online and offline content, and the third is the Ringtones.

Networks, calls and connectivity

Xiaomi Redmi Note 4 has a dual-SIM card tray with hybrid functions. It can house either a micro-SIM and a nano-SIM card, or a micro-SIM and a microSD card in case you need more storage. The two slots work with 4G LTE Cat. 6 networks in a dual-standby mode. The model supports a wide range of network bands, including 2G GSM (850, 900, 1800, 1900 MHz), 2.5G CDMA 800 MHz, 3G TD-SCDMA (1880-1920 and 2010-2025 MHz) and WCDMA (850, 900, 1700, 1900, 2100 MHz), 4G FDD-LTE (900, 1800, 1900, 2100, 2600 MHz) and 4G TDD-LTE (1900, 2300, 2500, 2600 MHz) networks as well as VoLTE. There have been no issues with call quality and reception whatsoever. Unlike Redmi Pro, in Redmi Note 4 you get more advanced Wi-Fi connectivity - dual-band, 802.11 a/b/g/n/ac. The rest of the wireless connectivity options include Wi-Fi Direct, Wi-Fi Hotspot, Wi-Fi Display, Bluetooth 4.2 and an infrared port. Wi-Fi and Bluetooth connections are established quickly and easily. However, there is no pre-installed app for the infrared port. You have to download one of your choice in order to use it. Otherwise, the IR blaster is fully functional. The micro-USB 2.0 port works fine, no OTG support. The model works with GPS, Glonass and Beidou and our review unit has managed to detect a good number of satellites from all three with very good accuracy.

Performance

Xiaomi Redmi Note 4 is the fifth device based on a deca-core MediaTek Helio X20 MT6797 chipset that we review. The most noteworthy feature of this system-on-chip is its three-cluster architecture, created with two goals in mind - intelligently switch between the three clusters depending on the load, so it optimizes both performance and power efficiency. The chipset includes two 2.1GHz Cortex-A72 cores, four 2GHz Cortex-A53 cores and another four of these, but clocked at 1.4GHz. There's a 700MHz quad-core Mali-T880 MP4 GPU as well, responsible for the graphics. Our review unit scored 84631 in AnTuTu, which is a bit less than the 87390 result of the Redmi Pro. During our review of the latter, we have already detected some issues with the GPU and not-so-optimized performance of the CPU. These confirm with the Redmi Note 4, which has results that are very close, but lower than those of the Redmi Pro, making it the slowest among the five Helio X20-based smartphones we have tested. Vernee Apollo Lite has scored 93030 in AnTuTu, Zopo Speed 8 has a result of 92644 points, and LeEco Le 2 (X620) has made 92374 during our test. It is the same with the results from all other benchmark tests we have performed. Only some of the 3DMark tests show a slightly better result than the one of the Redmi Pro, but the difference is only marginal. The RAM and storage of our review unit are less than those of the Redmi Pro - 2GB of LPDDR3 RAM clocked at 933MHz and 16GB of internal memory, respectively. However, the storage in Redmi Note 4 can be expanded with up to 128GB, while that of the Pro cannot be expanded. Of those 16GB, 10.56GB are available to the user. There's a version of the Redmi Note 4 with 3GB of RAM and 32GB of built-in memory. Storage scores of the two models in both PCMark's and Androbench's storage tests are very close and point to an eMMC 5.1 type of internal memory. Redmi Note 4 is equipped with a proximity, light, accelerometer, gyroscope, and Hall sensor as well as a rear-mounted fingerprint sensor made by FPC (FPC1035). It can be used for authorizing payments, viewing private documents, switch on children's mode, etc. If you've used another Xiaomi device before you already know that setting up a fingerprint ID is very easy and quick. Unlocking the device with it is fast.

Cameras

Xiaomi has tweaked the camera app in MIUI 8 by changing the appearance of some icons and relocating functions. The shortcuts to the HDR and flash shortcuts are moved to the top of the display, releasing space for the shortcuts to the switch between the cameras and the modes menu, which appear just above the main buttons. When you choose a specific mode, its settings appear above the big, circular shutter button. There are several modes to choose from, including panorama, beautify, HHT, scene choice, timer, audio, straighten, and manual mode. The latter applies for changes in the white balance and ISO. The list of modes has an icon to the camera settings. Both are different depending on which camera is on and which function it uses - taking photos or shooting videos. You can also edit a photo by applying filters to it, adding stickers, adjust the position or doodle it as well as enhance it by tweaking contrast, saturation, sharpness, etc.

Primary camera

The primary camera of Xiaomi Redmi Note 4 employs a 13-megapixel S5K3L8 sensor with a 1/3.06" format. It is coupled with a 5-element lens with an f/2.0 aperture, dual-tone LED flash and phase-detection autofocus. The camera outputs photos with a resolution of 4160 x 3120 pixels and is capable of shooting 1080p videos at 30 fps and 720p videos at 120 fps. The same camera sensor is provided in the Xiaomi Redmi 3 and the Redmi 3 Pro.

Secondary camera

The secondary camera's sensor of the Redmi Note 4 is the same as the one of the Redmi Pro - a 5-megapixel Samsung S5K5E8 CMOS BSI one. The selfie snapper also features an 85-degree wide-angle lens with an f/2.0 aperture and outputs images with a resolution of 2592 x 1944 pixels. It is also capable of making 720p videos at 30 fps. Other devices that we have reviewed and have the same sensor for their front camera are the Vernee Apollo Lite and Meizu m3 Note.

Audio

You're most probably familiar with the Music app from older MIUI versions. It is not changed at all in appearance and main functions. You can listen to music from your device, or choose to listen online, even download free and paid content, or even stream music. To use the online services, you must have an active MI account. The equalizer, grouping and ordering of audio files is the same and you can adapt them easily to your personal preferences. Of course you can also change the Headphones & audio effects settings directly from the Music app. We're glad to see that with the Redmi Note 4 Xiaomi is back on the right track as long as it concerns audio after we've seen the poor audio results of the Redmi Pro. The Note 4 excels not only in Frequency response, but also in Noise level and IMD+Noise, which is quite impressive for such a budget device. It also has Very good results in all other parameters, only the THD+Noise being evaluated as Good. More importantly, the values of the audio parameters can compete with those of more expensive smartphones. The single speaker, placed to the right of the USB 2.0 port in the bottom frame, sounds good. As usual, our audio test has been performed by using the TASCAM US-2x2 audio interface and the RightMark Audio Analyzer software.

Test	Value	RMAA rating
Frequency response (from 40 Hz to 15 kHz), dB	-0.03, -0.16	Excellent
Noise level, dB (A)	-96.9	Excellent
Dynamic range, dB (A)	91.6	Very good
THD, %	0.0036	Very good
THD + Noise, dB (A)	-83.5	Good
IMD + Noise, %	0.0078	Excellent
Stereo crosstalk, dB	-83.5	Very good
IMD at 10 kHz, %	0.014	Very good
General performance		Very good

Battery

The Power Efficiency app is a part of Xiaomi's Security app, which has been updated in MIUI 8. It no longer contains pre-set battery profiles, but has a Battery saver instead, which is switched off by default and you can choose. The Battery use tab provides more tools for power management and includes the battery monitor with information about, which hardware and apps consume the most power. The Settings icon of the Power app includes the Schedule power on & off, Battery indicator type, Battery drain and Heating notifications features as well as turn off mobile data and clear cache when the device is locked functions. You can also manage separate apps to optimize battery life. The app can also analyze battery usage and suggest optimizations. The main Settings menu includes a Battery & performance section, which actually has shortcuts to the Power Efficiency app and include several additional features such as choosing between a Balanced and a Performance battery profile or choose whether the device should show or hide the System animations. Xiaomi Redmi Note 4 is equipped with a 4100 mAh, Li Pol battery. It is non-removable and has a high-density of 713 Wh/L (Watt-hours/liter ). When we talk about energy density regarding batteries, we mean the amount of energy stored in a battery per unit volume. Put in other words, this the specific (volumetric) energy that defines volume in liters. Higher density, means longer battery life. A 5V/2A charger is also on board. The graph below displays the time needed for the battery to charge in full from 0% to 100% (the yellow line) and the temperature of the battery, while charging (the red line). A closer look reveals that the charging happens almost with even speed till the battery reaches 80%, when it slows down, and after 90% it slows even further. The total charging time is 2 hours and 35 minutes. The first 50% of the charge were reached in 1 hour and 5 minutes, the additional 40% to 90% needed another 52 minutes. While the last 10% to full capacity needed 33 minutes. The red line shows the change in battery temperature while charging. The top levels do not exceed 38 degrees Celsius, and they are reached when the battery is at 40% of its capacity. The temperature starts to slow down when the battery reaches 80% of its capacity. The PCMark Work battery life test showed a very good result of 9 hours. It is lower than the one of the Xiaomi Redmi Note 3 Pro, but this is due to the lower photo editing and video playing scores, otherwise, the device has almost the same results in web browsing and work performance, while in writing it surpasses the Redmi Note 3 Pro with a lot. The test has been performed in accordance with Futuremark's recommendation of calibrating the display's brightness to 200 cd/sq.m.

Final thoughts

If there has to be a final verdict in terms of comparing the Redmi Note 4 and the Redmi Pro, we think that the final cut will depend on the price. Both models have nearly identical design and solid build, run the latest MIUI 8, feature one and the same system-on-chip and almost identical batteries with identical performance. We like the Redmi Note 4 display best, though it is not OLED, and this model also has a very good audio. On the other hand, if you like OLED displays and prefer to have two rear cameras to tinker with, then the Pro is your choice. So, whether you should go for one model or the other, really depends on how much money you're ready to part with.