Design
- Decent looks, similar rainbow-like effects at the back as other Galaxy A series phone when caught against the light, and a prism-like pattern that Samsung calls a “3D prism design” - the design is been overused by Samsung
- While it supports a polycarbonate back, it still manages to look premium
- Compact and light for the display size and battery capacity, at just 185g, and 8.6mm in thickness
- The front has some thick bezels for the price
- The in-display fingerprint sensor, as well as the facial recognition, are on the slower side
- The glossy body is prone to picking up fingerprints
Display
- Sharp, bright 6.4-inches Super AMOLED panel with a full-HD+ resolution - its vivid colours make it a joy to stream content, while games also look great on the panel because of its high colour accuracy
- There's Widevine L1 support by default, which makes streaming content in HD possible
Software
- Comes with Android 10 out of the box - Samsung's One UI 2 is now one of the better, more clean and streamlined Android UIs around, and is well optimised for modern large displays (like this one)
- Samsung has also added some neat features including a Game Booster and an intuitive gesture-based navigation system
- There's still some bloatware pre-installed, including third-party apps and some of Samsung's own apps such as Samsung Shop (though most of them can be uninstalled)
Performance
- Average performance from the MediaTek Helio P65 - it feels a bit sluggish overall, there's a persistent hint of stutter in the animations, and lag when switching between apps
Camera
- Decent quad camera setup at the back - a 48MP primary sensor + 8MP wide-angle camera + 5MP macro camera + 5MP depth sensor
- Under good light, the Galaxy A31's primary camera manage to capture detailed shots with good dynamic range - images are reasonably sharp, noise is also competently removed, colours are generally nice, and the phone strikes a good balance with saturation
- The ultra wide-angle cam is decent at capturing more scene in the image (though, the quality is lower than the main camer)
- Macro camera turns out quite good close ups - you can get a lot closer to your subject when using the macro camera and the sensor picks up a fair bit of detail
- Very good portrait mode ("Live focus") - image quality is good and the depth camera helps the Galaxy A51 do a decent job of edge detection
- Photos from the 20MP front camera looks very impressive - selfies have plenty of detail and look really sharp, colors are pleasing, the dynamic range is impressive for a selfie camera - Selfie portraits are a thing on the A31 and surprisingly impressive - subject separation with a single camera is hard to pull off, and Samsung has done a great job of it
- No video stabilisation - video results are just average
- Low light photos out of the Galaxy A31 aren't great - the main camera's output is soft and noisy, while the colors are relatively desaturated
- Overall, while the Galaxy A51 offers good cameras, there are certainly better options available, such as the Redmi K20 Pro
Audio
- Decent bottom-firing speaker - sufficient for personal listening
Battery
- Good battery life from the 5000 mah battery - easily able to go well beyond a day on a single charge
- Reasonable 15W fast charging - charges 67 percent in an hour (though, not as quick as others in this segment such as the Redmi K20 Pro)
Verdict
- The Galaxy A31 has hardly anything going for it - the middling SoC performance and underwhelming cameras do nothing to help, there are better options available from Xiaomi and Realme