vivo X21 UD
The vivo X21 UD is a balanced everyday device, powered by the Qualcomm SDM660 Snapdragon 660 (14 nm), suited to light-to-moderate use (2018).
2018 · Lower-mid-range · Android 8.1 (Oreo)ⓘ Grades compare this device against others in its own market segment (Mid-range), not against every device on the site.
⚡ Quick Specs
Size6.28" · 154.5 x 74.8 x 7.4 mm (6.08 x 2.94 x 0.29 in)
ChipsetQualcomm SDM660 Snapdragon 660 (14 nm)
RAM6GB
Storage128GB
Main Camera12 MP · LED flash
⚖️ Compare With
✓︎ Pros
✓Sharp 402 PPI screen
✓6.28" OLED/AMOLED display with deep blacks and vibrant colours
✓Lightweight at 156.2g — easy to carry
✓3.5mm headphone jack for wired audio without adapters
⊗ Cons
✗Smaller 3,200 mAh battery — may need midday charging
✗Entry-level Qualcomm SDM660 Snapdragon 660 (14 nm) — struggles with demanding apps
✗12 MP main camera — basic quality, limited for photography enthusiasts
⚠️ Not ideal for
Heavy usage daysMobile gamingHeavy multitaskingPhotography
ℹ️ Overview
Announced
2018, March. Released 2018, March
⚙️ Performance
Chipset
Qualcomm SDM660 Snapdragon 660 (14 nm)
Mid-range — handles daily tasks well
CPU
Octa-core (4x2.2 GHz Kryo 260 Gold & 4x1.8 GHz Kryo 260 Silver)
OS
Android 8.1 (Oreo), Funtouch 4
RAM
6GB
Fine for everyday apps
💻 Display
Sharpness
402 ppi
Sharp and comfortable to read
Panel
Super AMOLED
OLED: perfect blacks, vivid colours, power-efficient
📷 Camera
Main Camera
12 MP
Capable for everyday photos
🔋 Battery
Capacity
3,200 mAh
May need midday charging with heavy use
Type
Li-Ion 3200 mAh, non-removable
📱 Design & Build
Weight
156.2g
Very light — comfortable for long use
Dimensions
154.5 x 74.8 x 7.4 mm (6.08 x 2.94 x 0.29 in)
Build
Glass front (Gorilla Glass 3), aluminum back, aluminum frame
Sensors
Fingerprint (under display, optical), accelerometer, proximity, compass
📶 Network
Speed
HSPA 42.2/5.76 Mbps, LTE (2CA) Cat6 300/50 Mbps
2G Bands
GSM 850 / 900 / 1800 / 1900
3G Bands
HSDPA 850 / 900 / 1900 / 2100
📡 Connectivity
WiFi
Wi-Fi 802.11 a/b/g/n/ac, dual-band, Wi-Fi Direct
❓ Frequently Asked Questions
No, the vivo X21 UD does not support 5G — it supports GSM / CDMA / HSPA / LTE.
No, the vivo X21 UD does not have NFC.
No, the vivo X21 UD charges via cable only — no wireless charging.
Yes, up to 18W (18W wired).
Yes, the vivo X21 UD supports microSDXC expandable storage.
The vivo X21 UD SIM configuration: Nano-SIM + Nano-SIM.
Yes, the vivo X21 UD has a 3.5mm headphone jack.
Speaker setup: Yes.
The vivo X21 UD ships with Android 8.1 (Oreo), Funtouch 4.
The vivo X21 UD uses microUSB 2.0, OTG.
The vivo X21 UD supports Wi-Fi 802.11 a/b/g/n/ac, dual-band, Wi-Fi Direct.
The vivo X21 UD has 5.0, A2DP, LE.
