Samsung Galaxy M31 Review — Minor yet worthy upgrade to Galaxy M30s

Samsung launched the Galaxy M31 smartphone in the ‘M Series’ in India last week as the successor of the M30s with upgraded cameras, Android 10 out of the box and 6GB RAM as a standard. Specifications look great on paper. Is the phone worth the price of Rs. 14,999? What do you have to compromise in this phone? Let us dive into the review to find out.

Box Contents

  • Samsung Galaxy M31 smartphone 6GB RAM, 128GB storage version in Space Black
  • 2-pin 15W (9V-1.67A / 5V-2A) fast charger
  • USB Type-C Cable
  • Quick Start Guide and Warranty information

Display, Hardware and Design

The new Galaxy M31 comes with a 6.4-inch Full HD+  Infinity U display with a resolution of 1080×2340 pixels at about 402.6 PPI, aspect ratio of 19.5:9, same as the M30 and the M30s. The display looks bright, thanks to 420 nits brightness, offers good color reproduction and the sunlight legibility is good as well, thanks to AMOLED panel, it offers true blacks. The screen is protected by Corning  Gorilla Glass 3.

Similar to the other Samsung phones, there is Blue light filter that is said to reduce eye strain by limiting the amount of blue light emitted by the screen, You can set it for sunrise to sunset and also set a custom schedule. You can change font size and style and select apps that you want to use in the full screen aspect ratio. There is also dark mode, which can be enabled by turning on night mode, which looks great on the AMOLED screen. The phone doesn’t have DC dimming or low brightness anti-flicker mode that is present in some AMOLED screen phones in the price range. I didn’t notice any screen flicker issues in low brightness on the M30s.

It doesn’t have notification LED, but there is Always on display with tap to show option that shows the AOD screen for 10 seconds after you tap the screen. You can also set a schedule. There are a lot of options to choose from such as clocks, GIF or you can download any AOD from Themes section.

On the top, there is an 32-megapixel camera in the notch and the earpiece is present on the top edge.

There is also a tiny space in the top left corner for the proximity sensor and the phone also has an ambient light sensor, which the M30 and the M30s lacks. It has gyroscope and magnetic sensor, otherwise known as magnetometer for VR, but it doesn’t have a notification LED. There is a small chin below the screen, similar to most phones with a notch.

The phone has shiny plastic frame which feels a bit cheap, however it doesn’t slip out of your hands easily. On the right side, there is a power button and the volume rockers. On the left side there is a single tray that houses dual nano SIM slots and a microSD card slot that accepts cards up to 512GB. At the bottom, there is a 3.5mm audio jack, USB Type-C port, loudspeaker grill and the primary microphone.

It is a good thing that Samsung has provided dedicated dual SIM and microSD card slots when there are a lot of phones that come with hybrid SIM arrangement.

On the back, there is a quad  camera module arranged in a rectangular array. There is single LED flash next to the camera module, and a fingerprint sensor next to it. Even though the phone has a huge 6.4-inch screen, it is compact to hold. It is 8.9 mm compared to 8.8mm M30s and weighs 191 grams, compared to 188g M30s.  The plastic back attract fingerprints and smudges easily and is also prone to scratches on day-to-day use. It is recommended to get a case since Samsung doesn’t provide one in the box. Overall the build quality is average compared to Samsung’s A series phones. It is not splash resistant like some phones in the price range.


It has a 64-megapixel rear camera with Samsung GW1 ISOCELL Bright sensor, 0.8μm pixel size and f/1.8 aperture, PDAF along with an 8-megapixel 123-degree ultra-wide lens with f/2.2 aperture, a 5-megapixel depth sensor with f/2.2 aperture and a 5-megapixel macro sensor with f/2.2 aperture. The phone has a 32-megapixel camera on the front with Sony IMX616 sensor with f/2.0 aperture. There is Live Focus that makes use of the 5-megapixel depth sensor. You can also adjust the bokeh effect before or after the shot. There is selfie portrait option for the front camera that uses software to blur the background. There is also a wide-angle option for the front camera.

It has Auto mode, Food, Night, Panorama, Macro, Pro, Live Focus, Super Slow-mo, Slow motion and Hyperlapse as well as Pro mode to adjust ISO, white balance and exposure manually, but you can’t adjust the shutter speed or focus. You can choose 64MP option from the aspect ratio settings on the top. It also has AR stickers that lets you add stickers. It also has scene optimizer, which is AI mode that automatically detects 20 modes.

There is partial Cam2API support and there is no RAW support for Exynos devices. I tried some APKs for Exynos, which crashed.

Coming to the image quality, daylight shots are good, and the camera captures a good amount of detail, creates well exposed photos with good dynamic range and detailing, and dynamic range can further be improved enabling HDR mode from the settings, which automatically turns on HDR when needed. Even though the phone has a 64-megapixel sensor, the final output has 16-megapixel resolution, which is common in phones with large sensors.

Autofocus speeds are fast and accurate. Macro shots are good as well, and there is a dedicated macro mode, but there is no touch to focus option in this mode. Live focus is good at detecting edges, and the wide-angle lens is useful in several places.  Even though the edges look a bit curved due to the lens, ‘Shape Correction’ is automatically applied that automatically crop the edges, still some images look a bit curved at the corners, which is common in wide-angle lenses. Low-light performance is decent, which can be improved further with Night mode that offers more details, but you need to keep your hand steady, since it takes two to three seconds to process. However, images shot using night mode are zoomed, and are captured in 8-megapixel resolution compared to 16-megapixel. 64-megapixel shots have good amount of details, but it takes time to process and is about 10MB in size. Images with flash is good even in closeups and is not over powering.

The 32-megapixel front camera is good in most case. Wide-angle mode takes images in 12-megapixel resolution after pixel binning, while the normal mode takes images in 8-megapixel. Software blur in the live focus mode doesn’t have good edge detection since it blurs some parts.

Check out some camera samples (Click the image for the full resolution sample).

It can record videos at maximum 4K resolution at 30 fps. There is also 1080p 30fps both in main and wide-angle camera, but there is no 1080p 60fps option, which is a restriction due to processor. It can shoot slow motion at 720p at 240fps and there is also super slow motion, which shoots an 8-second video with 6 seconds of slow motion, and also lets you add custom music for the slow motion part. You can also enable EIS for 1080p videos. Video quality is good, and the audio crisp since it has a secondary microphone. Check out the video samples below.

Software, UI and Apps

Coming to the software, the phone runs on Android 10 with Android security patch for February 2020. On the top of Android 10, it has Samsung One UI 2.0, which brings several features, but it still doesn’t have screen recording option.

The advanced features option has Games Launcher that gathers your games downloaded from Play Store and Galaxy Apps into one place for easy access, smart pop-up view, smart capture, direct share, motion gestures like lift to wake, double tap to wake, smart stay, easy mute by putting your hand over the screen or turning your phone face down, one-handed mode that lets you use the phone easily with one hand, finger sensor gestures to open and close the notification panel using the fingerprint sensor, palm swipe screenshot capture, swipe to call or send messages. Panic mode lets you Send SOS message by pressing the Power key three times and more.

The Device maintenance option lets you manage your device’s battery life, storage, RAM usage, and security all in one place. Out of 128GB (UFS 2.1) in our unit, 111GB is free. Out of 6GB LPDDR4x RAM, about 5.5GB is usable and 3GB is free when default apps are running in the background. Since this has UFS 2.1 storage, we got sequential read speeds of about 487MB/s.

Apart from the usual set of utility apps and Google Apps, the smartphone comes with Facebook app, Netflix app and Microsoft App OneDrive. You get option to install apps when you are setting up the phone, which you can choose not to. As a part of cost-cutting, the Samsung Galaxy M series phones don’t have Samsung Pay, Samsung Pass, Secure Folder, Bixby Voice/Vision, Samsung Cloud, Kids Mode, Easy Mode and Samsung Knox.

Fingerprint Sensor and Face unlock

The fingerprint sensor is present on the back, similar to most Samsung phones. It immediately unlocks phone just by keeping your finger so that you don’t have to press it. You can add up to 3 fingerprints, and adding fingerprint is easily with few swipes. It has support for Face recognition, which doesn’t work well if the lighting is poor in the room, if you are hats, or use heavy makeup, but it is quick to unlock the phone. It also asks if you are wearing sunglasses and says, “if you wear sunglasses most of the time, put them on for better results.”

Music Player and FM Radio

YouTube Music is the default music player. It has equalizer, Dolby Atmos, UHQ upscaler, Surround and Tube Amp Pro sound effects that can be enabled from the settings. All these improve the audio when listening through earphones. It has FM Radio support with support for recording. That said, audio through third-party headphones is good. Loudspeaker output from the mono speaker is good as well.

The phone comes with Widevine L1 support out-of-the-box so that you can enjoy HD content on Hotstar, Amazon Prime Video, Netflix and other streaming apps.

Dual SIM and Connectivity

The connectivity options include, Wi-Fi 802.11 ac (2.4GHz + 5GHz) with VoWiFi for Jio and Airtel, Bluetooth v5 and GPS with GLONASS. It has support for USB OTG. It has 4G connectivity with support a lot of bands and has Voice-over-LTE (VoLTE) support for Reliance Jio, Airtel and more.The dialer and messaging have familiar UI. Since this is a dual SIM phone, you get option to select either SIMs when calling or sending text message. Moving on, the call quality is good, and we did not face any call drops and the earpiece volume was loud. Speaker output during calls were good as well.

Performance and Benchmarks

It is powered by Exynos 9611 Octa-Core (Quad 2.3GHz A73 + Quad 1.7GHz A53) SoC , same as the M30s. The performance was smooth during daily usage, and enabling ‘reduce animations’ from the settings improves it further, since it reduces motion effects on the screen, such as when the apps are opened or close. RAM management was good as well.

With the Mali-G72MP3 GPU, the gaming experience was good. PUBG Works in HDR, but there are frame drops. Other mid-range games were smooth without much frame drops. The phone doesn’t get heated up on normal usage, but it is slightly warm when gaming. Check out some synthetic benchmark scores below.

As you can see the scores, it is clear that the SoC is placed towards the end compared to other Snapdragon SoCs, and the Exynos struggles in GPU scores, which we felt when gaming if you play games in high settings.

Battery life

The 6000mAh battery offers brilliant battery life that lasts more than a day with heavy use. With average use it lasted close to two days. I got about 8 hours of screen on time during my use with use of camera and social apps mostly on Wi-Fi and occasional 4G use for 2 days. Adaptive battery saving and other options will let you increase the battery life, but the performance might be affected.

In our One Charge rating, the Samsung Galaxy M31 scored 18 hours 49 minutes, which is slightly better than the M30s, which might be due to Android 10. Samsung has offered USB Type-C and 15W fast charging, while some offer 18W, 20W and even 30W charging. Charging with the bundled charger takes over 2 hours and 30 minutes to reach 100% from 0%, and 0 to 50% took about an hour, which is decent for a phone with a 6000mAh battery.


Overall, the Galaxy M31, is a good upgrade to last year’s M30s at competitive starting price of Rs. 14,999. It has upgraded cameras, while retaining the same AMOLED display and the huge 6000mAh battery, and most importantly comes with an ambient light snesor for brightness adjustment. Average low-light camera performance, plastic body and lack of Samsung Pay, Secure Folder, Samsung Knox are few things that needs to be compromised.


At the same price, the Redmi Note 8 Pro offers slightly better cameras and a better gaming experience. The POCO X2 is that costs slightly more offers 120Hz screen.The realme 6 that will be launched this week should be in the similar price range offering 90Hz refresh rate screen.


The Galaxy M31 comes in Ocean Blue and Space Black colors, is priced at Rs. 14,999 for the 6GB RAM with 64GB storage and Rs. 15,999 for the 6GB RAM with 128GB storage version. It will be available from starting from today, March 5th.


  • Good FHD+ Super AMOLED display
  • Good battery life
  • Good cameras
  • Dedicated Dual SIM and microSD Slots


  • Plastic back is prone to scratches
  • No screen recorder yet
  • Average low-light camera performance

Author: Srivatsan Sridhar

Srivatsan Sridhar is a Mobile Technology Enthusiast who is passionate about Mobile phones and Mobile apps. He uses the phones he reviews as his main phone. You can follow him on Twitter and Instagram