Samsung Galaxy S21 Ultra 5G vs Xiaomi Redmi A2

Samsung Galaxy S21 Ultra 5G

Xiaomi Redmi A2

Network
2G network

GSM 850, 900, 1800, 1900; CDMA 800, 1900 & TD-SCDMA

GSM 850, 900, 1800, 1900
3G network

HSDPA 850, 900, 1700(AWS), 1900, 2100; CDMA2000 1xEV-DO

HSDPA 850, 900, 2100
4G network

LTE frequency band 1, 2, 3, 4, 5, 7, 8, 12, 13, 14, 18, 19, 20, 25, 26, 28, 30, 38, 39, 40, 41, 46, 48, 66, 71

LTE frequency band 1, 3, 5, 7, 8, 20, 28, 38, 40, 41 - global version; 1, 3, 5, 8, 40, 41 - India
5G network

5G band SA/NSA/Sub6/mmWave

-
HSDPA speed

42.2 Mbps

-
HSUPA speed

5.76 Mbps

-
EV-DO speed

-

EV-DO Rev.A 3.1 Mbps download, 1.8 Mbps upload
LTE speed

LTE-A (CA), 2000 Mbps download, 200 Mbps upload

LTE
GPRS

Yes

Yes
EDGE

Yes

Yes

Design
Build

Glass front (Gorilla Glass Victus), glass back (Gorilla Glass), aluminum frame

Plastic
SIM

Single SIM (Nano-SIM and/or eSIM) or Dual SIM (Nano-SIM and/or eSIM, dual stand-by)

Dual SIM (Nano-SIM, dual stand-by)
Height

165.1 mm

164.9 mm
Width

75.6 mm

76.8 mm
Thickness

8.9 mm

9.1 mm
Weight

227 (Sub6) / 229 (mmWave) g

192 g
Payment

Samsung Pay (Visa, MasterCard certified)

-
Waterproof

IP68 (1.5m and 30 mins)

-
Dust proof

IP68

-
Colors

Black, Brown, Silver, Navy, Titanium

Black, Blue, Green

Display
Display type

Dynamic AMOLED 2X

IPS LCD
Physical size

6.8 inches

6.52 inches
Resolution

1440 x 3200 pixels

720 x 1600 pixels
Pixel density

515 ppi

269 ppi
Display colors

16777216

16777216
Protection

Scratch resistant, Corning Gorilla Glass Victus

Scratch resistant, 2.5D curved glass screen
Display features

120Hz, HDR10+, 1500 nits (peak), Infinity-O display, Always-On display

400 nits (typ)
DxOMark display score

91

-

Main camera
Camera type

Quad

Dual
Main camera

(wide) , 108 MP, f/1.8 , 26 mm, 1/1.33" , 0.8 µm

(wide) , 8 MP, f/2.0
(periscope telephoto) , 10 MP, f/4.9 , 1/3.24" , 1.22 µm, 10x optical zoom

(depth) , 0.08 MP
(telephoto) , 10 MP, f/2.4 , 70 mm, 1/3.24" , 1.22 µm, 3x optical zoom
(ultrawide) , 12 MP, f/2.2 , 13 mm, 1/2.55" , 1.4 µm
Primary camera resolution

12000 x 9000 pixels

3264 x 2448 pixels
Primary camera video

8K@24fps, 4K@30/60fps, 1080p@30/60/240fps, 720p@960fps, HDR10+, stereo sound rec., gyro-EIS

1080p@30fps
Primary camera flash

LED flash

dual-LED flash
Camera features

Autofocus, continuous shooting, digital zoom, optical zoom, optical image stabilization, geotagging, panorama, HDR, touch focus, face detection, white balance settings, ISO settings, exposure compensation, self-timer, scene-mode, phase detection autofocus, laser autofocus

Autofocus, digital zoom, digital image stabilization, geotagging, panorama, HDR, touch focus, face detection, white balance settings, ISO settings, exposure compensation, self-timer, scene-mode, macro-mode, phase detection autofocus
DxOMark photo

128

-
DxOMark zoom

76

-
DxOMark video

98

-
DxOMark camera score

121

-

Selfie camera
Selfie camera type

-

Single
Selfie camera

(wide) , 40 MP, f/2.2 , 80˚ , 26 mm, 1/2.8" , 0.7 µm

5 MP, f/2.2
Selfie camera resolution

7968 x 5480 pixels

2560 x 1944 pixels
Selfie camera features

Autofocus, HDR, phase detection autofocus

Face unlock
Selfie camera video

4K@30/60fps, 1080p@30fps

1080p@30fps
DxOMark photo

105

-
DxOMark video

93

-
DxOMark camera score

100

-

Connectivity
WLAN

Wi-Fi 802.11a, 802.11b, 802.11g, 802.11n, 802.11n 5GHz, 802.11ac, 802.11ax, 6E

Wi-Fi 802.11a, 802.11b, 802.11g, 802.11n, 802.11n 5GHz
WLAN WiFi Hotspot

Yes

Yes
WLAN WiFi Direct

Yes

Yes
WLAN WiFi Dual Band

Yes

Yes
USB

Type-C 3.2

microUSB 2.0
USB On-The-Go

Yes

-
Bluetooth

v5.2

v5.0
Bluetooth A2DP

Yes

Yes
bluetooth LE

Yes

Yes
NFC

Yes

No
GPS

Yes, with A-GPS

Yes, with A-GPS
GLONASS

Yes

Yes
GALILEO

Yes

Yes
BDS

Yes

Yes