Compare phones
| Global Score | |
| 85.5 | 76.1 |
| Basic Information | |
| Samsung | Samsung |
| Android 11, 10 | Android 10 |
| 2019-12-27 | 2020-06-29 |
| 6.24 x 2.90 x 0.31 inches | 6.61 x 3.02 x 0.32 inches |
| 6.07 ounces | 6.81 ounces |
| Prism Crush black, Prism Crush blue, Prism Crush pink and Prism Crush white | Black |
| Plastic and Plastic | Plastic and Plastic |
| Scratch-Resistant Glass | -- |
| $ 282.00 | $ 194.00 |
| Display / Screen | |
| 6.5 inches | 6.5 inches |
| 2400 x 1080 pixels | 1600 x 720 pixels |
| Super AMOLED | IPS LCD |
| 405 pixels per inch | 270 pixels per inch |
| No touch screen | No touch screen |
| 8.1 | 7.3 |
| Performance | |
| Samsung Exynos 9611 chipset | Mediatek Helio P35 chipset |
| ARM Cortex-A73 and ARM Cortex-A53, 64-bit, 10 nm (Octa-Core 2300 MHz) processor | Arm Cortex-A53, 64-bit, 12 nm (Octa-Core 2300 MHz) processor |
| 4 GB RAM | 3 GB RAM |
| Mali-G72 MP3 GPU | PowerVR GE8320 GPU |
| 9.27 | 9.27 |
| Storage | |
| 128 GB internal memory | 32 GB internal memory |
| microSDXC (up to 512 GB) external memory slot | microSDXC (up to 512 GB) external memory slot |
| 14.14 | 9.84 |
| Camera | |
| 48.00 MP + 32.00 MP | 16.00 MP + 13.00 MP |
| f/2.00 aperture | f/1.80 aperture |
| 26.00mm focal length | -- |
| 0.5 inches (1/2") sensor | 0.33 inches (1/3.06") sensor |
| 3840 x 2160 (30 fps) (4K) video resolution | 1920 x 1080 (30 fps) (Full HD) video resolution |
| 1280 x 720 (240 fps) (HD) slow motion video | -- |
| 11.55 | 9.35 |
| Networks | |
| Wi-Fi | Wi-Fi |
| Mobile Hotspot | Mobile Hotspot |
| LTE-A (4G), LTE (4G), HSPA+ (4G), HSDPA and HSUPA | LTE-A (4G), LTE (4G), HSPA+ (4G), HSDPA and HSUPA |
| Nano SIM, Dual SIM | Nano SIM |
| 6.7 | 6.7 |
| Battery Life | |
| 4000mAh Li - Polymer Battery | 4000mAh Li - Polymer Battery |
| Non-Removable Battery | Non-Removable Battery |
| 5.92 | 5.92 |
| Other Features | |
| Bluetooth 5.0 | Bluetooth 5.0 |
| GPS | GPS |
| NFC | NFC |
| Fingerprint ID Scanner | Fingerprint ID Scanner |
| Accelerometer, Compass, Gyroscope, Light Sensor and Proximity Sensor | Accelerometer, Compass, Gyroscope, Light Sensor and Proximity Sensor |
| FM Radio | FM Radio |
Comparison review
Galaxy A51 is better than Galaxy A21, having an 85.5 score against 76.1. The Galaxy A51 is a somewhat lighter and just a bit thinner phone than Galaxy A21, although both of them were released with only a couple of months difference. Both of these devices have Android operating system, but Galaxy A51 has newer 11 version while Galaxy A21 has Android 10, so it gives you some additional features and performance enhancements.
Galaxy A21's processor is just as good as the processing unit in Galaxy A51, and although the Galaxy A21 has a lower amount of RAM memory, they both have a Octa-Core processing unit. The Galaxy A51 has a much better screen than Samsung Galaxy A21, and although they both have a display of the same size, the Galaxy A51 also has a better quantity of pixels per inch of display and a lot higher 1080 x 2400 resolution.
The Samsung Galaxy A51 counts with a greater camera than Galaxy A21, because although it has a smaller aperture which is not favorable for low light images, it also counts with a way higher 3840x2160 video resolution, a much larger sensor and a back-facing camera with a lot better resolution. Galaxy A51 counts with a much better memory to install applications and games than Samsung Galaxy A21, and although they both have an external SD slot that allows a maximum of 512 GB, the Galaxy A51 also has 128 GB internal storage capacity.
Galaxy A21 has a battery lifetime that is just as good as the battery life in Samsung Galaxy A51.
The Galaxy A51 is way more expensive than Samsung Galaxy A21, but you can get a better phone for that few extra dollars.
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