Screen size
C100iWinner: 6.8"+4.4%
C216.5"
Quick verdict
C100i leads the measured specs 9-6.
Measured wins
C100i
9
spec wins
Overall winner
Ties
7
equal specs
C21
6
spec wins
Screen size
Technology
C100i
GSM / HSPA / LTE
C21
GSM / HSPA / LTE
2G bands
C100i
GSM 850 / 900 / 1800 / 1900
C21
GSM 850 / 900 / 1800 / 1900
3G bands
C100i
HSDPA 850 / 900 / 2100
C21
HSDPA 850 / 900 / 2100
4G bands
C100i
1, 3, 5, 7, 8, 20, 28, 38, 40, 41
Resolution
Refresh rate
Peak brightness
Pixel density
CPU speed
RAM
Storage
Main camera
Front camera
equal specsBattery
Wired charging
Weight
Thickness
IP rating
Wi‑Fi
Bluetooth
equal specsUSB
equal specs5G support
equal specsNFC
equal specs3.5mm jack
equal specsSD card
equal specsStereo speakers
C21
1, 3, 5, 7, 8, 20, 28, 38, 40, 41 - International, 1, 3, 5, 8, 38, 40, 41 - India
Speed
C100i
HSPA, LTE
C21
HSPA, LTE
Announced
C100i
2026, April 30
C21
2021, March 05
Status
C100i
Released May 7, 2026
C21
Available. Released 2021, March 05
Dimensions
C100i
166.5 x 78.2 x 8.4 mm (6.56 x 3.08 x 0.33 in)
C21
165.2 x 76.4 x 8.9 mm (6.50 x 3.01 x 0.35 in)
Weight
C100i
208 g (7.34 oz)
C21
190 g (6.70 oz)
Build
C100i
Glass front, plastic frame, plastic back
C21
Glass front, plastic back, plastic frame
SIM
C100i
Nano-SIM + Nano-SIM
C21
Nano-SIM + Nano-SIM
Other
C100i
IP64 dust tight and water resistant (water splashes) Drop resistant up to 2m MIL-STD-810H compliant* * does not guarantee ruggedness or use in extreme conditions
C21
-
Type
C100i
IPS LCD, 120Hz
C21
IPS LCD, 400 nits (typ)
Size
C100i
6.8 inches, 113.0 cm2 (~86.8% screen-to-body ratio)
C21
6.5 inches, 102.0 cm2 (~80.8% screen-to-body ratio)
Resolution
C100i
720 x 1570 pixels, 19.5:9 ratio (~254 ppi density)
C21
720 x 1600 pixels, 20:9 ratio (~270 ppi density)
Protection
C100i
Panda MN228 or Corning Gorilla Glass
C21
-
OS
C100i
Android 16
C21
Android 10, Realme UI
Chipset
C100i
Unisoc T7250 (12 nm)
C21
Mediatek MT6765G Helio G35 (12 nm)
CPU
C100i
Octa-core (2x1.8 GHz Cortex-A75 & 6x1.6 GHz Cortex-A55)
C21
Octa-core (4x2.3 GHz Cortex-A53 & 4x1.8 GHz Cortex-A53)
GPU
C100i
Mali-G57 MP1
C21
PowerVR GE8320
Card slot
C100i
microSDXC
C21
microSDXC (dedicated slot)
Internal
C100i
64GB 4GB RAM, 128GB 4GB RAM, 128GB 6GB RAM
C21
32GB 3GB RAM, 64GB 4GB RAM
Other
C100i
eMMC 5.1
C21
eMMC 5.1
Single
C100i
8 MP, f/2.0, (wide), AF
C21
-
Features
C100i
LED flash, HDR, panorama
C21
LED flash, HDR, panorama
Video
C100i
1080p@30fps
C21
1080p@30fps
Dual
C100i
-
C21
13 MP, f/2.2, 26mm (wide), 1/3.06", 1.12µm, PDAF 2 MP (macro) Auxiliary lens
Single
C100i
5 MP, f/2.2, (wide)
C21
5 MP, f/2.2, (wide), 1/5.0", 1.12µm
Video
C100i
720p@30fps
C21
1080p@30fps
Features
C100i
-
C21
HDR, panorama
Loudspeaker
C100i
Yes
C21
Yes
3.5mm jack
C100i
Yes
C21
Yes
WLAN
C100i
Wi-Fi 802.11 a/b/g/n/ac, dual-band
C21
Wi-Fi 802.11 b/g/n
Bluetooth
C100i
5.2, A2DP, LE
C21
5.0, A2DP, LE
Positioning
C100i
GPS, GALILEO, GLONASS, BDS
C21
GPS, GLONASS, BDS
NFC
C100i
No
C21
No
Radio
C100i
Unspecified
C21
FM radio
USB
C100i
USB Type-C 2.0, OTG
C21
microUSB 2.0, OTG
Sensors
C100i
Fingerprint (side-mounted), accelerometer, gyro, proximity, compass
C21
Fingerprint (rear-mounted), accelerometer, proximity, compass
Type
C100i
Si/C Li-Ion 7000 mAh
C21
5000 mAh
Charging
C100i
15W wired, PD, QC Reverse wired
C21
10W wired Reverse wired
Colors
C100i
Dawn Purple, Dusk Gray
C21
Cross Black, Cross Blue
Models
C100i
RMX5377
C21
RMX3201
Price
C100i
About 110 EUR
C21
About 410 EUR