Screen size
X21 UD6.3"
Y500iWinner: 6.8"+7%
Quick verdict
Y500i leads the measured specs 11-8.
Measured wins
X21 UD
8
spec wins
Ties
3
equal specs
Y500i
11
spec wins
Overall winner
Screen size
Technology
X21 UD
GSM / CDMA / HSPA / LTE
Y500i
GSM / CDMA / HSPA / LTE / 5G
2G bands
X21 UD
GSM 850 / 900 / 1800 / 1900 , CDMA 800 & TD-SCDMA
Y500i
GSM 850 / 900 / 1800 / 1900 , CDMA 800
3G bands
X21 UD
HSDPA 850 / 900 / 1900 / 2100
Y500i
HSDPA 850 / 900 / 2100
4G bands
X21 UD
1, 2, 3, 5, 8, 34, 38, 39, 40, 41
Resolution
Refresh rate
Peak brightness
Pixel density
CPU speed
equal specsRAM
Storage
equal specsMain camera
Front camera
Battery
Wired charging
Weight
Thickness
IP rating
Wi‑Fi
Bluetooth
USB
equal specs5G support
NFC
3.5mm jack
SD card
Stereo speakers
Y500i
1, 3, 5, 8, 28, 34, 38, 39, 40, 41
Speed
X21 UD
HSPA 42.2/5.76 Mbps, LTE (2CA) Cat6 300/50 Mbps
Y500i
HSPA, LTE, 5G
5G bands
X21 UD
-
Y500i
1, 3, 5, 8, 28, 38, 40, 41, 77, 78 SA/NSA
Announced
X21 UD
2018, March. Released 2018, March
Y500i
2026, January 12
Status
X21 UD
Discontinued
Y500i
Available. Released 2026, January 16
Dimensions
X21 UD
154.5 x 74.8 x 7.4 mm (6.08 x 2.94 x 0.29 in)
Y500i
166.6 x 78.4 x 8.4 mm (6.56 x 3.09 x 0.33 in)
Weight
X21 UD
156.2 g (5.50 oz)
Y500i
219 g (7.72 oz)
Build
X21 UD
Glass front (Gorilla Glass 3), aluminum back, aluminum frame
Y500i
Glass front, plastic frame, plastic back
SIM
X21 UD
Nano-SIM + Nano-SIM
Y500i
Nano-SIM + Nano-SIM
Other
X21 UD
-
Y500i
IP68/IP69 dust tight and water resistant (high pressure water jets; immersible up to 1.5m for 30 min)
Type
X21 UD
Super AMOLED
Y500i
IPS LCD, 120Hz, 1000 nits (HBM), 1200 nits (peak)
Size
X21 UD
6.28 inches, 98.4 cm2 (~85.2% screen-to-body ratio)
Y500i
6.75 inches, 111.4 cm2 (~85.3% screen-to-body ratio)
Resolution
X21 UD
1080 x 2280 pixels, 19:9 ratio (~402 ppi density)
Y500i
720 x 1570 pixels, 19.5:9 ratio (~256 ppi density)
Protection
X21 UD
Corning Gorilla Glass 3
Y500i
-
OS
X21 UD
Android 8.1 (Oreo), Funtouch 4
Y500i
Android 16, OriginOS 6
Chipset
X21 UD
Qualcomm SDM660 Snapdragon 660 (14 nm)
Y500i
Qualcomm SM4450 Snapdragon 4 Gen 2 (4 nm)
CPU
X21 UD
Octa-core (4x2.2 GHz Kryo 260 Gold & 4x1.8 GHz Kryo 260 Silver)
Y500i
Octa-core (2x2.2 GHz Cortex-A78 & 6x1.95 GHz Cortex-A55)
GPU
X21 UD
Adreno 512
Y500i
Adreno 613
Card slot
X21 UD
microSDXC (uses shared SIM slot)
Y500i
No
Internal
X21 UD
128GB 6GB RAM
Y500i
128GB 8GB RAM, 256GB 8GB RAM, 256GB 12GB RAM, 512GB 8GB RAM, 512GB 12GB RAM
Other
X21 UD
eMMC 5.1
Y500i
UFS 3.1
Dual
X21 UD
12 MP, f/1.8, 1/2.55", 1.4µm, dual pixel PDAF Auxiliary lens
Y500i
-
Features
X21 UD
LED flash, HDR, panorama
Y500i
LED flash, HDR, panorama
Video
X21 UD
1080p@30fps
Y500i
1080p@30fps
Single
X21 UD
-
Y500i
50 MP, f/1.8, (wide), PDAF
Single
X21 UD
12 MP, f/2.0, (wide), 1/2.8", 1.28µm
Y500i
5 MP, f/2.0, (wide)
Video
X21 UD
1080p@30fps
Y500i
1080p@30fps
Loudspeaker
X21 UD
Yes
Y500i
Yes, with stereo speakers
3.5mm jack
X21 UD
Yes
Y500i
No
Other
X21 UD
32-bit/192kHz Hi-Res audio
Y500i
-
WLAN
X21 UD
Wi-Fi 802.11 a/b/g/n/ac, dual-band, Wi-Fi Direct
Y500i
Wi-Fi 802.11 a/b/g/n/ac, dual-band
Bluetooth
X21 UD
5.0, A2DP, LE
Y500i
4.2, A2DP, aptX Adaptive
Positioning
X21 UD
GPS, GLONASS
Y500i
GPS, GALILEO, GLONASS, BDS, QZSS
NFC
X21 UD
No
Y500i
Yes
Radio
X21 UD
FM radio
Y500i
No
USB
X21 UD
microUSB 2.0, OTG
Y500i
USB Type-C 2.0, OTG
Infrared port
X21 UD
-
Y500i
Yes
Sensors
X21 UD
Fingerprint (under display, optical), accelerometer, proximity, compass
Y500i
Fingerprint (side-mounted), accelerometer, proximity, compass
Type
X21 UD
Li-Ion 3200 mAh, non-removable
Y500i
Si/C Li-Ion 7200 mAh
Charging
X21 UD
18W wired
Y500i
44W wired Reverse wired
Colors
X21 UD
Black, Ruby Red
Y500i
Black, Silver, Gold
Models
X21 UD
X21UD A
Y500i
V2531A
Price
X21 UD
About 550 EUR
Y500i
About 180 EUR