BLU Studio C vs vivo X21 UD

Compare recorded specifications, size and practical differences.

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Key differences

Calculated from recorded specifications using minimum difference thresholds. These are differences, not an overall ranking. For three phones, numeric highlights compare the two extremes.

  • Display technology

    OLED versus LCD

    Studio C:
    LCD
    X21 UD:
    OLED
  • Weight

    X21 UD: 15.8 g lighter

    Studio C:
    172 g
    X21 UD:
    156.2 g
  • Width

    Studio C: 2.4 mm narrower

    Studio C:
    72.4 mm
    X21 UD:
    74.8 mm
  • Screen diagonal

    Studio C: 1.28 in smaller diagonal

    Studio C:
    5 in
    X21 UD:
    6.28 in
  • Chipset

    Studio C:
    Mediatek MT6582 (28 nm)
    X21 UD:
    Qualcomm SDM660 Snapdragon 660 (14 nm)
  • Rear camera layout

    Studio C:
    Single
    X21 UD:
    Dual

Physical size

Relative size, not calibrated actual size. Front and side outlines share one scale and a bottom baseline. Generic outlines use recorded body dimensions, excluding camera bumps.

  1. 1. Studio C

    Height:
    144 mm
    Width:
    72.4 mm
    Depth:
    9.4 mm +2 mm versus X21 UD
  2. 2. X21 UD

    Height:
    154.5 mm +10.5 mm versus Studio C
    Width:
    74.8 mm +2.4 mm versus Studio C
    Depth:
    7.4 mm

Weight

Bars start at zero and share a scale within this chart.

  1. 1. Studio C

    172 g

    +15.8 g versus X21 UD

  2. 2. X21 UD

    156.2 g

Screen size

Approximate rectangular screens calculated from recorded diagonal and aspect ratio at one relative scale. Rounded corners and cutouts are not subtracted. These are not phone outlines or calibrated actual sizes.

  1. 1. Studio C

    Screen diagonal:
    5 in
    Aspect ratio (height:width):
    16:9
    Approximate rectangular screen area:
    68.9 cm²
  2. 2. X21 UD

    Screen diagonal:
    6.28 in
    Aspect ratio (height:width):
    19:9
    Approximate rectangular screen area:
    98.4 cm²

X21 UD has approximately 42.8% more rectangular screen area than Studio C.

Memory variants

Each row compares the same storage capacity. Cells show recorded RAM alternatives, not combined maxima. Not recorded does not mean unavailable in every market.

Recorded RAM for Studio C, X21 UD, compared at the same storage capacity.
StorageStudio CX21 UD
8 GB 1 GB RAM Not recorded
128 GB Not recorded 6 GB RAM

Practical features

Explicit Yes and No values are shown directly. Qualified or regional records retain their details. Unknown means the record is missing.

1. Studio C

NFC:
Unknown
Headphone jack:
Yes
Memory card support:
See details microSD · up to 64 GB

2. X21 UD

NFC:
Unknown
Headphone jack:
Yes
Memory card support:
See details microSD · up to 256 GB (uses SIM 2 slot)

Battery capacity

Capacity is not battery life. No endurance test is implied.

Recorded battery capacity

Bars start at zero and share a scale within this chart.

  1. 1. Studio C

    3000 mAh

  2. 2. X21 UD

    3200 mAh

    +200 mAh versus Studio C

Specifications

Open a section for more detail. On narrow screens, swipe sideways or use Left/Right arrow keys while the table is focused. Unknown means missing data, not No. Recorded zero values are shown as recorded.

1. Studio C2. X21 UD

Everyday essentials
Everyday essentials — specifications for Studio C, X21 UD.
SpecificationStudio CX21 UD
Dimensions (HxWxD)
  • 144 Х 72.4 Х 9.4 mm
  • 154.5 Х 74.8 Х 7.4 mm
Weight
  • 172 g
  • 156.2 g
Technology
  • IPS LCD
  • Super AMOLED
Screen size
  • 5" inch
  • 6.28" inch
Screen resolution
  • 720 x 1280 px
  • 1080 x 2280 px
Internal memory Recorded storage / RAM variants. Entries are alternatives, not a combined maximum. Ambiguous formats stay as recorded.
  • 8 GB
  • 1 GB RAM
  • 128 GB
  • 6 GB RAM
Memory card support
  • microSD
  • up to 64 GB
  • microSD
  • up to 256 GB (uses SIM 2 slot)
Battery Capacity is not battery life. No endurance test is implied.
  • 3000 mAh
  • Removable Li-Ion
  • 3200 mAh
  • Non-removable Li-Ion
Operating system OS
  • Android 5.0 (Lollipop)
  • Android 8.1 (Oreo); Funtouch 4
Chipset
  • Mediatek MT6582 (28 nm)
  • Qualcomm SDM660 Snapdragon 660 (14 nm)
Headphone jack
  • Yes
  • Yes
Display
Display — specifications for Studio C, X21 UD.
SpecificationStudio CX21 UD
Touchscreen
  • capacitive touchscreen
  • capacitive touchscreen
Display colors
  • 16M
  • 16M
Screen area
  • 68.9 cm2
  • 98.4 cm2
Screen format
  • 16:9 (height:width)
  • 19:9 (height:width)
Screen to body ratio
  • 66.1%
  • 85.2%
PPI /points per inch/
  • 294 PPI
  • 402 PPI
Camera and Video
Camera and Video — specifications for Studio C, X21 UD.
SpecificationStudio CX21 UD
Rear camera, main
  • 8 MP
  • Single
  • 12 MP
  • Dual
Camera specs
  • 8 MP
  • AF
  • 12 MP
  • f/1.8
  • 1/2.55''
  • 1.4µm
  • dual pixel PDAF -5 MP
  • f/2.4
  • depth sensor
Functions
  • LED flash
  • HDR
  • LED flash
  • HDR
  • panorama
Video
  • 1080p@30fps
  • 1080p@30fps
Front camera, selfie
  • 2 MP
  • Single
  • 12 MP
  • Single
Specifications
  • 2 MP
  • 12 MP
  • f/2.0
Performance

Scores marked * are historical catalogue entries. Test conditions are unspecified; no new testing is implied.

Performance — specifications for Studio C, X21 UD.
SpecificationStudio CX21 UD
Processor CPU
  • Quad-core 1.3 GHz Cortex-A7
  • Octa-core (4x2.2 GHz Kryo 260 & 4x1.8 GHz Kryo 260)
Graphics processor GPU
  • Mali-400MP2
  • Adreno 512
Antutu 7 score * Unknown
  • 143592
General specs
General specs — specifications for Studio C, X21 UD.
SpecificationStudio CX21 UD
Release date
  • 2015
  • May
  • 2018
  • March
Colors
  • Sandstone Grey
  • Ceramic White
  • Salmon Pink
  • Mint Green
  • Atomic Orange
  • Black
  • Ruby Red
Historical recorded price Legacy catalogue value; date unknown. Not a current offer. Unknown
  • 550 EUR
Battery life
  • Stand by time- Up to 980 h (2G) / Up to 890 h (3G) Talking time- Up to 40 h (2G) / Up to 24 h (3G)
Unknown
Body build Unknown
  • Front glass
  • aluminum body
Communication and Connectivity
Communication and Connectivity — specifications for Studio C, X21 UD.
SpecificationStudio CX21 UD
SIM card
  • Dual SIM (Mini-SIM)
  • Hybrid Dual SIM (Nano-SIM
  • dual stand-by)
Network
  • Show all network frequencies: -2G - GSM 850 / 900 / 1800 / 1900 - SIM 1 & SIM 2
  • Show all network frequencies: -2G - GSM 850 / 900 / 1800 / 1900 - SIM 1 & SIM 2 CDMA 800 & TD-SCDMA -3G - HSDPA 850 / 900 / 1900 / 2100 -4G - LTE band 1(2100)
  • 2(1900)
  • 3(1800)
  • 5(850)
  • 8(900)
  • 34(2000)
  • 38(2600)
  • 39(1900)
  • 40(2300)
  • 41(2500)
Speed
  • HSPA 21.1/5.76 Mbps
  • HSPA 42.2/5.76 Mbps
  • LTE-A (2CA) Cat6 300/50 Mbps
GPRS
  • Class 12
  • Yes
Edge
  • Class 12
  • Yes
Wi-Fi
  • Wi-Fi 802.11 b/g/n
  • Wi-Fi Direct
  • hotspot
  • Wi-Fi 802.11 a/b/g/n/ac
  • dual-band
  • WiFi Direct
  • hotspot
GPS
  • Yes
  • with A-GPS
  • Yes
  • with A-GPS
  • GLONASS
USB
  • microUSB 2.0
  • microUSB 2.0
  • USB On-The-Go
Bluetooth
  • 4.0
  • A2DP
  • 5.0
  • A2DP
  • LE
Music and Audio
Music and Audio — specifications for Studio C, X21 UD.
SpecificationStudio CX21 UD
Radio
  • Stereo FM radio
  • FM radio
Others Unknown
  • 32-bit/192kHz audio -Active noise cancellation with dedicated mic
Other features
Other features — specifications for Studio C, X21 UD.
SpecificationStudio CX21 UD
Dop
  • Sensors Accelerometer
  • proximity
  • Sensors Fingerprint (under display)
  • accelerometer
  • proximity
  • compass - Fast battery charging