Xiaomi Redmi Pro Review

Being one of the latest Xiaomi smartphones, along with the Redmi Note 4, the Redmi Pro is the fourth Xiaomi device we receive for testing and we're eager to discover this model along with you, revealing gradually its specifications in depth. This smartphone is particularly interesting, because it looks like that with it Xiaomi has aimed to create the perfect all-rounder. It has thrown in several high-end features such as an OLED display, a Helio X20 chipset and a large battery - 4050 mAh. At the same time the manufacturer has managed to retain a very reasonable price tag (USD 220-290 depending on the retailer). This review is a good way to check whether there is consistency in what the manufacturer offers for your bucks as all Xiaomi models up to now excelled in that.

Specifications

Xiaomi Redmi Pro is equipped with a 5.5-inch OLED display with a resolution of 1080 x 1920 pixels and a pixel density of 401 ppi. It has a static contrast ratio of 60000:1 and covers 100% of the NTSC color space. On top of it is placed a 2.5D curved glass layer. Under the hood ticks a MediaTek Helio X20 MT6797 system-on-chip, created after the 20nm process. It has a tri-cluster architecture to provide a combination of optimum performance and power efficiency. The chipset includes two Cortex-A72 CPU cores clocked at 2.1GHz, four Cortex-A53 CPU cores clocked at 2GHz and another quadruplet of Cortex-A53 cores clocked at 1.4GHz. They are coupled with a 700 MHz quad-core ARM Mali-T880 MP4 GPU. The Exclusive and the High Editions pack a MediaTek Helio X25 MT6797T chipset, which has its pair of Cortex-A72 cores clocked at a higher rate - 2.5GHz for the Exclusive and 2.3GHz for the High Edition. The clock rate of the GPU is also increased to 850MHz and 780MHz, respectively. The RAM and storage also depend on the model's variant. The Standard and the High Edition arrive with 3GB of LPDDR4, dual-channel RAM clocked at 1866MHz. The Exclusive Edition has 4GB of the same type of RAM. The internal memory measures 32GB, 64GB, and 128GB for the Standard, High, and Exclusive Edition, respectively. In all three cases the storage is expandable. The chipset supports a large variety of connectivity options, including dual-band Wi-Fi 802.11 b/g/n, Wi-Fi Hotspot, Wi-Fi Direct, Wi-Fi Display, Bluetooth 4.2, USB Type-C 2.0, USB OTG, GPS, Glonass, BeiDou. As long as it concerns call networks, these include 2G GSM, 2.5G CDMA, 3G WCDMA and TD-SCDMA, and 4G TDD-/FDD-LTE Cat. 6 with VoLTE. There's a fingerprint sensor embedded in the home button, which is the same one installed on the Xiaomi Mi 5. The rest of the supported sensors include proximity, light, accelerometer, compass, gyroscope, Hall. The camera department has an interesting setup that includes two shooters on the back. The main one packs a 13-megapixel Sony IMX258 Exmor RS sensor, ImagiQ depth of field image processor, and a 5-element lens with an f/2.0 aperture. The second rear camera is equipped with a 5-megapixel Samsung S5K5E8 CMOS BSI with a 5-element lens. Both are aided by a dual-tone LED flash. The front-facing camera has the same sensor as the second rear shooter - a 5MP Samsung S5K5E8 one, but coupled with a different lens that has an 85° wide angle and an f/2.0 aperture. Finally, the model features a high-density, 4050 mAh Lithium-Polymer battery that is non removable and is coupled with a 5V/2A fast charger. For the full list of Xiaomi Redmi Pro Standard Edition specifications you can check the model's page.

What's in the box

Xiaomi Redmi Pro arrives in a traditional white Xiaomi box with a photo of the model on top, the MI logo and the name of the model. On the back of the box you'll find information about some basic specifications, supported networks and official certifications of the device. The smartphone is in the top level compartment of the box and under it are the user manual, warranty card, SIM tray pin, a Type-C to USB cable, and a two-pin wall charger (US NEMA-1 plug standard). The latter means that the charger has two flat pins and no grounding area. This standard is used in the US, Canada and some Latin American countries, so you will most probably need an adapter for the plug if you live elsewhere.

Design, build and controls

Xiaomi Redmi Pro has a metal body crafted from aluminum alloy with a brushed effect on the back. It has CNC chamfered edges, which are glossy and contrast with the matte finish. The back has a slight curve towards its vertical edges as to provide a better and more comfortable grip. The front panel with the 2.5D curved display unit protrudes with a millimeter or two above the edge of the frame, which helps the smartphone to create a very slim visual profile, though it is 8.15 mm thick. This is actually a bit below average for smartphones with a 5.5-inch display and 4000 mAh batteries. The model's weight of 174 grams is also typical for such a smartphone. In addition, the device is 76.2 mm wide, which falls within the normal width for a 5.5-inch smartphone, but results in very thick borders - both from the front panel and the screen bezels. Redmi Pro is 151.5 mm high, which is a compact height for the class. It is available in three colors - gold, grey with a black front and silver with a white front. We are reviewing a silver unit. The controls layout is typical for Redmi smartphones. On the left the hybrid, dual-SIM tray is placed, while on the right a volume rocker and a power button below it are located. The tray opens and closes smoothly and the metal buttons provide excellent tactile experience, while fitting perfectly into their places. Actually, the whole feeling of the device is that it is very solid. On the top of the frame there are a microphone, 3.5 mm jack, and infrared port. On the bottom one there are symmetrical grille holes - the left ones are for a microphone, the right ones are for the speaker. In between them, centrally positioned is the USB Type-C 2.0 port. On the front above the display are placed an LED notification light, the earpiece, proximity sensor and front-facing camera. Below the display Xiaomi has provided a high-quality ceramic home button with an embedded fingerprint sensor - like the one in Xiaomi Mi 5. The menu and back buttons are capacitive backlit dots. The whole navigation bar behaviour can be managed from the corresponding options in the Settings menu - a typical feature of MIUI. On the rear you'll see two thin, horizontal antenna bands - one for the top and one for the bottom. Under the top one, vertically across the center, there are the main camera module, a horizontal dual-tone LED flash (the warm light is on the left), and the second camera module. Towards the bottom end of the back is the MI logo.

Display

Xiaomi Redmi Pro is the first smartphone of the manufacturer that features an OLED display, it is even more interesting to test it, having in mind that usually OLED and AMOLED displays are placed in mid-to-high-end devices that cost more. When you come to think of OLED/AMOLED, you will most definitely associate it with Samsung, which is a market leader in this type of displays with a 95% market share, followed by LG and others. However, Xiaomi has opted for a domestic supplier called EverDisplay. If this primary supplier cannot make it, then Xiaomi will rely on its secondary choice - BOE. Actually, EverDisplay Optronics (a.k.a. Hehui Optoelectronics) might not be familiar to the western world, but it is very well-known in Asia and the company plans to invest USD 4.1 billion to build a 6-Gen AMOLED factory by 2019, with test production starting in 2018. BOE Display actually specializes in TFT/LCD displays and has only recently ventured into the production of OLED/AMOLED screens and since last year it has started the construction of an LCD/AMOLED production unit with an investment of USD 3.5 billion, which should be finished in 2017. Xiaomi Redmi Pro features a 5.5-inch OLED display with an FHD resolution (1080 x 1920), which results in a pixel density of 401 ppi. The official specifications point at 60000:1 static contrast ratio and 100% coverage of the NTSC color space. OLED stands for organic light-emitting diode. In such displays, an electroluminescent layer of organic semiconductors is placed between two electrodes and emits light as a reaction to an electric current. This means the OLED displays work without a backlight, hence, they are lighter and thinner than LCD displays. They also have a couple of specific features, the first of which is their capability to transfer more power to each pixel, when the white portion displayed on the screen is smaller. That's why in order to grasp more correctly the brightness value of any OLED and AMOLED display, we use the Average Picture Level (APL), which is the percentage of white on the display that is lit up compared to a full white display. Thus, we are able to make measurements at different in size portions of the screen that display white color and follow up how the white luminance at one and the same brightness percentage changes depending on the portion of the display that is lit up. Below you see the APL graph for the Xiaomi Redmi Pro, which shows how the white luminance drops when measured on a 1/10 of the display to a full white image (100% APL). At 10% APL the peak brightness reaches 450 cd/sq.m., while at 100% APL (full white image), the peak white luminance measures 320 cd/sq.m. The second specific feature of OLED/AMOLED displays is their ability to display very deep black color, very often referred to as "infinite black". This is due to the fact that in order to show the black color, OLED displays simply switch off the corresponding pixels. Hence, the actual black levels cannot be measured by regular tools and, logically, the contrast ratio cannot my mathematically derived. The temperature of the white point of Redmi Pro's display is high and is in the range from 8600K to 9400K. In case you like your display to show warmer colors, you can tweak the temperature from the Display settings.

Brightness	White luminance	Black luminance	Contrast	Color temperature
100 %	322.178 cd/m2	0.000 cd/m2	-	9420 K
75 %	265.826 cd/m2	0.000 cd/m2	-	9322 K
50 %	196.90 cd/m2	0.000 cd/m2	-	9167 K
25 %	88.419 cd/m2	0.000 cd/m2	-	8870 K
0 %	9.783 cd/m2	0.000 cd/m2	-	8559 K

The pixel geometry of Xiaomi Redmi Pro's display is type Delta (a.k.a. triangular), because the red, blue and green components form a triangular/delta shape. With 100% coverage of the NTSC color space, it is expected that the display will have strong saturation and deviation in color. Indeed, the CIE diagram shows a huge deviation in the green area, high in the blue one and average in the red area. The colors are over-saturated and in some cases incorrect - for example the red in some app icons looks orange. Tweaking the colors from the Display settings improve things a bit. Viewing angles are excellent with only slight loss in brightness when the display is looked at from aside.

OS, UI and software

Xiaomi Redmi Pro is currently sold in China and online retailers that ship internationally pre-load Google Play Services. The unit we have received runs MIUI 8 based on Android 6.0 Marshmallow. The exact version of the ROM is V8.0.1.0.MHQCNDG. This is the Chinese version as currently there is no international version of MIUI 8 for this model. However, the retailer has pre-installed Google Play Services. MIUI 8 is not very different from MIUI 7. It is deeply customized and builds upon the previous versions. First differences we came across is that there is no Wallpaper Carousel and from the Settings menu you can customize the shortcuts that appear on the lock screen. By default it only displays a shortcut to the camera app on the lower right corner. The music app (when active) and notifications appear on the lock screen as well by default. A swipe up unlocks the device and opens the home screen. All Xiaomi devices provide a very good choice of themes and wallpapers. The ones for Redmi Pro do not differ from those on MIUI 7, but this is not a pain as there are many themes and wallpapers available for free download and you can access them from the corresponding apps and settings. For starters, there is a Themes app, which provides access to online and offline themes and wallpapers. The latter can be accessed from the Widgets and Wallpapers menu and from the Settings>Themes/Wallpaper menus. By default, if you zoom in with two fingers on the home screen, this opens the Widgets menu. It can also be accessed if you tap and hold the left button on the capacitive navigation bar. Just like in the previous versions of MIUI, it has an extensive range of options that includes a tool for re-arranging the apps and folders on the screens. The Widgets options allow you to add on the home screen and the following ones toggles from the Quick Menu, from the Settings and other useful apps such as the Cleaner. The Wallpapers menu lets you choose from several offline options and there's a link to the online galleries. The fourth option is called Effects and lets you choose the effect with which screens/apps open and close. There's an icon to the right of the clock widget and after you press it you get access to several styles of clocks to choose from. A third difference with former MIUI versions is the way the notifications appear. This time they are merged with the quick settings. The whole shade area includes weather information on the top, quick settings toggles (which are scrolled to the left and right), the brightness level bar below them and the notifications. There's a Settings shortcut icon, too. A simple tap on the left navigation button opens the list of running apps with a "clear all" option. If you swipe down an app, you get two choices - either to lock it or get more information about it. Unlocking happens after a swipe up on the locked up. The rest is the same as in previous versions of the software. A long press on the home button opens the "Ok, Google" voice search. The back button has no additional functions unless you choose such from the Buttons menu under Additional settings. Another difference is the Volume menu, which looks more like the original Marshmallow one, unlike in MIUI 7 where the different volume profiles appeared separately depending on the app and the volume icon was a circle. If you press longer the power button you'll access the Power off menu. The Settings menu of MIUI 8 has gone some restructuring compared to MIUI 7 and is less colorful. The icons in front of the menus and simpler and of one color, so are the toggles and active menus (light blue). However, the deep customization is preserved. Moreover, unlike other MIUI versions, there's a search bar above the list with Settings, which lets you search among them and ultimately get faster access to desired options. The first group of options is the connectivity one - SIM card management, Wi-Fi and Bluetooth connections, but this time the developers have added another feature, which appears a step up in the menu - the Personal Hotspot. Under WLAN options you can manage advanced Wi-Fi options such as Wi-Fi Direct, Wi-Fi display and WPS options. The second section of the Settings is called Personal unlike in MIUI 7 where it was named Device. This remains the most extensive group of options and in MIUI 8 it starts with Display, which switches places with the Notifications and status bar settings. Under Display you can set up the Reading mode, color temperature and contrast among all else. Them the Wallpaper and Themes option follow, which duplicate the ones from the Themes app and the Widgets menu. The Sound & vibration menu is changed with the various types of volumes brought a level up and not hidden under a Volume folder. The number of volumes is decreased to three from five and there's a Silent Mode toggle for quick access. Lock screen & password is the following group of options from where you can set types of locks, set up and manage fingerprint IDs. This provides an additional option to choose what type of shortcuts should appear on the lock screen. There are also options to choose from when you use Xiaomi's smartcover with your device. Setting up a fingerprint ID is very easy. Unlocking is amazingly fast. However, if the device is locked with the screen off, you have to press the home button and this simultaneously recognizes your fingerprint and unlocks the smartphone. The following menu manages the Notifications & status bar. It has added an option for you to choose whether the notifications and quick menu toggles should appear together (by default in MIUI 8) or should appear separately as in previous software versions. The rest of the options are the same and include app notification management, changing toggle positions in the quick menu, and choosing the way icons appear on the status bar. And now we arrive to a very interesting feature called Second Space. If you choose this option, the phone will load a "second space" - this is like a virtual machine on the same device, which is fully functional. For people, who want to manage two sets of apps, IDs and so on, this might turn out a very useful feature. The DND mode settings are enriched with options for setting up time for the various modes. The storage is self explanatory, while the Battery & performance has also been enriched with several features, which we will discuss in the Battery section of this review. Both are taken out from the Additional settings menu compared to MIUI 7. There's a Lite mode of the UI, which you're familiar with from the previous MIUI versions. It is intended for users who are visually impaired or need a simpler interface with larger icons for quick access under specific occasions. The Additional settings menu is the last one from the Personal group of options. It is also very extensive and is restructured compared to the one of MIUI 8. The Privacy and Child mode options are grouped in a sub-group, while the first one includes Date & time, Language & input, and Locale. Xiaomi developers have added something called Quick Ball, which in its essence is a floating dot with shortcuts to a back function, home screen, device lock, screenshot, and list with running apps. Actually, it duplicates the navigation bar in terms of functions, but you can change those shortcuts to your preference. As usual, you can manage the notification light, navigation bar buttons, headphones and audio effects, one-handed mode, accessibility, and the Mi Mover function. The Accounts group of settings includes the typical menu for the MI account, a second section for all other accounts on the phone, and sync data options. A new feature is the Google account set of options, which lacks in MIUI 7 and appears now in the 8th version of the software. The last group of options, which has been known as System up to now, is called App Settings and includes a list with system apps and a second one with installed apps and detailed options for each one of the apps on the device. These options can be also accessed from the Settings icon that appears in every app once you open it. There's a new function in this section called Dual apps - it allows you to use one and the same app with different settings. Icons of dual apps appear differently on the home screen. The Permissions and App Lock menus from the Security app are also inserted in the App Settings group of options. The last menu is the classic About Phone with a System updates icon at the bottom. The unit we have received is not overloaded with pre-installed apps, though typical for MIUI there's a number of tools on board, but we will get to them later. Xiaomi developers have preserved the classic MIUI look with apps appearing on the home and successive screens. Moving an app to the recycle bin means you'll uninstall it, but a confirmation prompt appears prior to finalizing the actions, so you cannot uninstall an app by mistake. On the home screen you also get by default the Ok, Google search and the clock widget, which you can remove simply by pressing and holding on them and moving them to the trash icon that appears. You can also switch their places. There's a row of docked apps on the home screen, including the Dialer, Messenger, default Browser, and Camera, unlike in MIUI 7, where this list includes Dialer, Contacts, Browser and Messenger. However, in MIUI 8 the Phone Dialer and Contacts are merged into one app, though there are two separate icons for them leading to the corresponding sections inside the app. Above them are the Gallery, Settings, Themes, Security, Play Store, Weather apps as well as Google and Tools folder. On the second desktop are placed a folder with More apps, Calendar, Notes, Explorer, Music, SIM Toolkit and Mi Remote. The More apps contains the SwiftKey keyboard app. The Google folder contains only Gmail and Voice search, while the Tools one is where you'll find the Contacts, Calculator, Clock, Mail, FM Radio, Mi Account, Recorder, Updater, Feedback, Scanner, Downloads, and Compass. 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 Clock and Compass remain unchanged, while the Gallery app offers a new way of grouping the photos, the most interesting one being the face recognition. MI Remote is a classic Xiaomi app for all smartphones of the company, which are equipped with an IR blaster. There are lots of apps for free download that will do the same job, but this one arrives pre-installed and includes a large number of brands and models of home appliances - from TVs and set top boxes to air conditioners and refrigerators. The app works fine and is easy to use. The Explorer has also remained unchanged, while the Notes app has been entirely redesigned. The Security app includes six main features - Cleaner, which removes duplicate and unnecessary files to save storage, Data usage manager, Blocklist, Battery manager, Virus Scan, and app Permissions. It is the same found in MIUI 7. The Themes app is self-explanatory, so is the Updater. The Voice recorder is improved and now can output voice to text in a document.

Networks, calls and connectivity

Xiaomi Redmi Pro is equipped with a hybrid, dual-SIM card tray, which houses either a micro-SIM and a nano-SIM, or a micro-SIM and a microSD card. Both slots support 4G LTE Cat. 6 connectivity and work 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 UMTS (850, 900, 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. The device provides excellent call quality, both for the caller and recipient. Network reception has been steady at all times. The wireless connectivity options of the model include dual-band Wi-Fi 802.11 b/g/n, Wi-Fi Direct, Wi-Fi Hotspot, Wi-Fi Display, Bluetooth 4.2 and an infrared port. Our review unit managed to detect Wi-Fi signal fairly well even in areas, where usually other devices struggle to do so. The IR blaster works fine and the MI Remote app managed to detect a nearby TV very quickly. The wireless display function works fine as well and when the connection is established you automatically get an additional option in the list of sharing functions for photos and other content on the device. The USB-Tpe-C 2.0 port provides OTG support and as long as it concerns satellite navigation, Redmi Pro works successfully with the main three systems - GPS, Glonass and Beidou. The device has managed to detect a good number of satellites from all three with excellent accuracy.

Performance

We are reviewing a Standard Edition of Xiaomi Redmi Pro, which runs on a MediaTek Helio X20 MT6797 chipset and is the fourth device we have reviewed that sports this SoC. The 20nm chipset has a tri-cluster architecture created to achieve two main goals - share the load in such a way as to maximize performance and power efficiency. More specifically, its CPU consists of 2x 2.1GHz Cortex-A72 cores, 4x 2GHz ACortex-A53 core, and 4x 1.4GHz Cortex-A53 cores. A 700 MHz quad-core Mali-T880 MP4 GPU handles the graphics. Our review unit scored 87390 in AnTuTu, thus, taking the fourth place after Vernee Apollo Lite, which scored 93030 in AnTuTu, Zopo Speed 8 with a result of 92644 points, and LeEco Le 2 (X620), which made 92374 during our test. А closer look at the result reveals that Xiaomi Redmi Pro actually leads all four according to the RAM score and is almost on par in CPU score with them. However, the 3D and UX results are noticeably low compared to those of the other three models and hence, the lower overall score. PCMark's Work performance score adds more details to the overall impressions. According to this test, of all four Zopo Speed 8 has the highest result - 5272, and Redmi Pro scored very close to it - 5229, while the other two models score less than 5000 points. PCMark's test is very reliable and worth paying attention to as it reveals results that simulate very closely real life ones. In the context of 3DMark's test the Redmi Pro is close to LeEco Le 2 (X620) and both yield to the results of the Zopo Speed 8 and Vernee Apollo Lite. Xiaomi Redmi Pro Standard Edition arrives with the latest generation of dual-channel, LPDDR4 RAM, which measures 3GB and is clocked at 1866MHz. This amount of RAM is more than enough, if you have a reasonable amount of apps installed and running in the background. Actually, at no point we have ever experienced any hiccups during our test period, so this type of chipset and RAM configuration is excellent for this device, including for playing games that are not heavy graphics demanding. The internal memory measures 32GB and there's no information about its type, but we suppose it is an older generation than eMMC 5.1 as memories of this generation provide sequential read speeds that are twice as fast as those shown by the Redmi Pro in the Androbench test. The other parameters are almost on par with the results of the other three devices, all of which have 32GB of eMMC 5.1 internal memory. Even the PCMark storage score shows a lower result for the Redmi Pro compared to the Vernee Apollo Lite. Of those 32GB, 26.81GB are available to the user. The smartphone has a number of sensors on board, all, or at least most of which made by Bosch - according to Aida64. They include an accelerometer, magnetic field, orientation, gyroscope, gravity, rotation sensor, and others. The ceramic home button has an integrated fingerprint sensor - the same one as in the Xiaomi Mi 5 - FPC1245. It is extremely fast, however, in order to unlock the device with the screen off, you have to press the home button to unlock the devce with your fingerprint.

Cameras

The camera app in MIUI 8 differs visually from that in MIUI 7. The big, circular shutter button along with the button for video and gallery are the same, but in MIUI 8 the shortcuts to HDR and the flash are moved to the upper right and left corners, respectively, while in their former places are placed shortcuts to the switch between the cameras and the modes menu. Information about the modes is displayed centrally above the shutter and above it, in the Redmi Pro is present another icon. It is called Stereo and lets you choose the aperture and the corresponding bokeh effect. Usually, the wider the aperture (the lower the f-number), the stronger the blur area and shallower the depth of field. The various modes include panorama, beautify, HHT, scene choice, timer, audio, straighten, and manual mode. The latter allows change in the white balance and ISO. The list of modes contains a shortcut icon to the camera settings. The modes list and settings are different for shooting photos and videos for both cameras - the front and back one. Let's have a more detailed look at how the two-camera setup of the Redmi Pro works. When you choose a specific aperture value from the Stereo mode, you activate both cameras, which take photos simultaneously. Then the software creates a "bokeh effect" corresponding to the aperture value you've chosen by making real-time calculations. People who are not into photography will most probably have fun tinkering with this option. However, people who know a bit more will not get into it very much. The "bokeh effect" is achieved artificially and in most cases the border between the focused and de-focused areas is clearly visible. Moreover, the bokeh does not look very natural and is very far away from what normal DSLR cameras can do, for example. Besides changing the aperture prior to taking a photo, you can also change it after taking it, but this is only possible for photos that are already done with this mode on. Below you can see an example, how a change in the aperture value changes the appearance of the photo. This Stereo mode can be applied prior and after shooting videos, as well. The photo edit mode is very extensive and also lets you add a number of background effects, change the 3D effect, add filters, rotate the photo, adjust its saturation, sharpness, brightness and contrast. There are also doodle options for some fun editing. There's a large choice of sharing options and if the Wi-FI Display function is on, you can also choose to cast the photo to your TV, for example.

Primary camera

So lets get down to specifics. The main rear camera of Xiaomi Redmi Pro is equipped with a 13-megapixel Sony IMX258 Exmor RS sensor and a 5-element lens with an f/2.0 aperture. They are aided by a dual-tone LED flash. The main camera takes advantage of a second ISP - MediaTek's ImagiQ image signal processor for dynamic depth of field. Actually, Elephone P9000 has the same camera sensor and you can check sample photos from our review of the device and compare them with those of the Redmi Pro. The images are with output resolution of 4160 x 3120 pixels and the camera can shoot FHD videos @ 30fps. The second rear camera features a 5-megapixel Samsung S5K5E8 CMOS BSI sensor and a 5-element lens.

Secondary camera

The front-facing camera has the same sensor as the second rear camera - a 5-megapixel Samsung S5K5E8 CMOS BSI one. It is coupled with an 85° wide-angle lens with an f/2.0 aperture. The camera makes images with a resolution of 2592 x 1944 pixels and HD videos. 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

The Music app has not been changed at all in MIUI 8. It provides access to both offline and online music content. The latter is accessible once you log in with your MI account. The app provides the standard listing and grouping of files as well as the standard equalizer, which has several pre-set audio profiles, each of which you can change to your own preference. There's also access to the Headphones & audio effects settings, which can be accessed from the Sound & vibration menu and the Headphones menu from the Settings. From this menu, you can set what function the remote buttons for your headphones should perform. You can also switch on the MI Sound Enhancer and choose the type of headphones you're using in order to get the proper audio boost. Unlike all other Xiaomi smartphones we have tested, the Redmi Pro does not impress at all in terms of audio. Actually, if you have a look at the results, they are quite mediocre. The overall score is Good, which is less than average. The device excels only in frequency response, while the noise level and stereo crosstalk are Very good. What affects the final result more is the Average score for dynamic range and THD + Noise along with the Good score for THD and IMD + Noise. As usual, our audio test has been performed by using the TASCAM US-2x2 audio interface and the RightMark Audio Analyzer software. The single speaker on board is placed behind the right grille at the bottom frame. It sounds OK, but nothing more than average.

Test	Value	RMAA rating
Frequency response (from 40 Hz to 15 kHz), dB	+0.01, -0.11	Excellent
Noise level, dB (A)	-94.2	Very good
Dynamic range, dB (A)	79.4	Average
THD, %	0.0019	Good
THD + Noise, dB (A)	-72.5	Average
IMD + Noise, %	0.029	Good
Stereo crosstalk, dB	-80.0	Very good
IMD at 10 kHz, %	0.033	Good
General performance		Good

Battery

Xiaomi Redmi Pro arrives with a new Power Efficiency app as part of its Security app, which has been changed in MIUI 8, compared to MIUI 7. For starters, it does not include pre-set battery profiles and profile switch options. Instead, you get only a Battery Saver and a schedule option when it should be turned on and off. The monitor is hidden under Battery Use, and includes more advanced status parameters such as mobile networks signal on, Wi-Fi and GPS on status, Awake, Screen on and Charging times. You can also check which apps and what hardware consume most power as well as restrict individual apps running in the background from the App battery saver. Clicking on the Settings icon within the Power apps opens various options that include Schedule power on & off, Battery indicator type, Battery drain and Heating notifications (both are new features), and two power-saving functions: turn off mobile data and clear cache when the device is locked. The app can also make an analysis of the battery usage and suggest optimizations. In addition, the Settings menu includes a Battery & performance section. Its first menu is called Power and actually opens the Power Efficiency app. The Battery Use one duplicates the second feature of the app - which app and what hardware consume the most power. The apps background restriction function is also duplicated in this menu under Manage apps' battery usage with the option to turn on and off this power saving mode. There are two functions such as the Power Settings, which lets you choose between a Balanced and a Performance battery profile, as well as the System animations, which by default are shown and you can choose to hide them in order to save more power. Xiaomi Redmi Pro packs a non-removable Li-Pol battery with a capacity of 4050 mAh. It is accompanied by a 5V/2A fast charger. The graph below displays the time needed for the battery to charge in full from 0% to 100% (see the yellow battery level line) and the temperature of the accumulator, while charging (check the red line). It clearly shows that the battery charges with an even pace till it reaches around 90% of its capacity, when the charging speed slows down. To be more precise, for the first 60% of the capacity the battery charged almost with 1% per minute as it needed 1 hour and 5 minutes to reach 60%. Then it slowed down slightly and needed 26 minutes to reach 80%. Another 15 minutes were needed to reach 90%, 12 minutes to reach 95% and the last 5% to reach full charge needed 23 minutes. The total charging time was 2 hours and 21 minutes. The red line depicts the battery temperature during the charging process. It is visible that its peak levels do not exceed 38 degrees Celsius and they are reached around 55% of charge and start to drop around 80% of the battery charge. The PCMark Work battery life test showed a very good result of 8 hours and 30 minutes, but it is actually lower than the one of the Xiaomi Redmi Note 3 Pro, which even has a slightly smaller battery capacity - 4000 mAh. The test has been performed in accordance with Futuremark's recommendation of calibrating the display's brightness to 200 cd/sq.m.

Final thoughts

The overall impression is that Xiaomi has done it again. It is one of the very few smartphone manufacturers that are consistent in offering value for money and the Redmi Pro is no exception. The USD 220-290 price tag might seem a bit high at a first glance, but hey, you get a 5.5-inch FHD OLED display, a 2.1GHz Helio X20 CPU, a dual rear camera setup, and a high-end fingerprint sensor coupled with the latest MIUI offering many software features and excellent build. If you haven't had a Xiaomi smartphone up to now and you want to try one, the Redmi Pro would be a perfect pick.