vivo X21 UD vs ZTE Boost MAX+

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

    X21 UD:
    OLED
    Boost MAX+:
    LCD
  • Weight

    X21 UD: 38.6 g lighter

    X21 UD:
    156.2 g
    Boost MAX+:
    194.8 g
  • Width

    X21 UD: 7.8 mm narrower

    X21 UD:
    74.8 mm
    Boost MAX+:
    82.6 mm
  • Screen diagonal

    Boost MAX+: 0.58 in smaller diagonal

    X21 UD:
    6.28 in
    Boost MAX+:
    5.7 in
  • Rear camera layout

    X21 UD:
    Dual
    Boost MAX+:
    Single
  • Depth

    X21 UD: 2.8 mm thinner

    X21 UD:
    7.4 mm
    Boost MAX+:
    10.2 mm

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. X21 UD

    Height:
    154.5 mm
    Width:
    74.8 mm
    Depth:
    7.4 mm
  2. 2. Boost MAX+

    Height:
    165.1 mm +10.6 mm versus X21 UD
    Width:
    82.6 mm +7.8 mm versus X21 UD
    Depth:
    10.2 mm +2.8 mm versus X21 UD

Weight

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

  1. 1. X21 UD

    156.2 g

  2. 2. Boost MAX+

    194.8 g

    +38.6 g versus X21 UD

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. X21 UD

    Screen diagonal:
    6.28 in
    Aspect ratio (height:width):
    19:9
    Approximate rectangular screen area:
    98.4 cm²
  2. 2. Boost MAX+

    Screen diagonal:
    5.7 in
    Aspect ratio (height:width):
    16:9
    Approximate rectangular screen area:
    89.6 cm²

X21 UD has approximately 9.9% more rectangular screen area than Boost MAX+.

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 X21 UD, Boost MAX+, compared at the same storage capacity.
StorageX21 UDBoost MAX+
16 GB Not recorded 2 GB RAM
128 GB 6 GB RAM Not recorded

Practical features

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

1. X21 UD

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

2. Boost MAX+

NFC:
Unknown
Headphone jack:
Yes
Memory card support:
No

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. X21 UD

    3200 mAh

  2. 2. Boost MAX+

    3400 mAh

    +200 mAh versus X21 UD

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. X21 UD2. Boost MAX+

Everyday essentials
Everyday essentials — specifications for X21 UD, Boost MAX+.
SpecificationX21 UDBoost MAX+
Dimensions (HxWxD)
  • 154.5 Х 74.8 Х 7.4 mm
  • 165.1 Х 82.6 Х 10.2 mm
Weight
  • 156.2 g
  • 194.8 g
Technology
  • Super AMOLED
  • IPS LCD
Screen size
  • 6.28" inch
  • 5.7" inch
Screen resolution
  • 1080 x 2280 px
  • 720 x 1280 px
Internal memory Recorded storage / RAM variants. Entries are alternatives, not a combined maximum. Ambiguous formats stay as recorded.
  • 128 GB
  • 6 GB RAM
  • 16 GB
  • 2 GB RAM
Memory card support
  • microSD
  • up to 256 GB (uses SIM 2 slot)
  • No
Battery Capacity is not battery life. No endurance test is implied.
  • 3200 mAh
  • Non-removable Li-Ion
  • 3400 mAh
  • Non-removable Li-Ion
Operating system OS
  • Android 8.1 (Oreo); Funtouch 4
  • Android 5.1 (Lollipop)
Chipset
  • Qualcomm SDM660 Snapdragon 660 (14 nm)
Unknown
Headphone jack
  • Yes
  • Yes
Display
Display — specifications for X21 UD, Boost MAX+.
SpecificationX21 UDBoost MAX+
Touchscreen
  • capacitive touchscreen
  • capacitive touchscreen
Display colors
  • 16M
  • 16M
Screen area
  • 98.4 cm2
  • 89.6 cm2
Screen format
  • 19:9 (height:width)
  • 16:9 (height:width)
Screen to body ratio
  • 85.2%
  • 65.7%
PPI /points per inch/
  • 402 PPI
  • 258 PPI
Screen protection Unknown
  • Corning Gorilla Glass
Camera and Video
Camera and Video — specifications for X21 UD, Boost MAX+.
SpecificationX21 UDBoost MAX+
Rear camera, main
  • 12 MP
  • Dual
  • 8 MP
  • Single
Camera specs
  • 12 MP
  • f/1.8
  • 1/2.55''
  • 1.4µm
  • dual pixel PDAF -5 MP
  • f/2.4
  • depth sensor
  • 8 MP
Functions
  • LED flash
  • HDR
  • panorama
Unknown
Video
  • 1080p@30fps
  • 720p
Front camera, selfie
  • 12 MP
  • Single
  • 1 MP
  • Single
Specifications
  • 12 MP
  • f/2.0
  • 1 MP
Performance

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

Performance — specifications for X21 UD, Boost MAX+.
SpecificationX21 UDBoost MAX+
Processor CPU
  • Octa-core (4x2.2 GHz Kryo 260 & 4x1.8 GHz Kryo 260)
  • Quad-core 1.2 GHz
Graphics processor GPU
  • Adreno 512
Unknown
Antutu 7 score *
  • 143592
Unknown
General specs
General specs — specifications for X21 UD, Boost MAX+.
SpecificationX21 UDBoost MAX+
Release date
  • 2018
  • March
  • 2015
  • July
Colors
  • Black
  • Ruby Red
  • Gold
Historical recorded price Legacy catalogue value; date unknown. Not a current offer.
  • 550 EUR
  • 180 EUR
Battery life Unknown
  • Talking time- Up to 16 h (3G)
Body build
  • Front glass
  • aluminum body
Unknown
Communication and Connectivity
Communication and Connectivity — specifications for X21 UD, Boost MAX+.
SpecificationX21 UDBoost MAX+
SIM card
  • Hybrid Dual SIM (Nano-SIM
  • dual stand-by)
  • Micro-SIM
Network
  • 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)
  • Show all network frequencies: -2G - GSM 850 / 900 / 1800 / 1900 -3G - HSDPA -4G - LTE
Speed
  • HSPA 42.2/5.76 Mbps
  • LTE-A (2CA) Cat6 300/50 Mbps
  • HSPA
  • LTE
GPRS
  • Yes
  • Yes
Edge
  • Yes
  • Yes
Wi-Fi
  • Wi-Fi 802.11 a/b/g/n/ac
  • dual-band
  • WiFi Direct
  • hotspot
  • Wi-Fi 802.11 b/g/n
  • hotspot
GPS
  • Yes
  • with A-GPS
  • GLONASS
  • Yes
  • with A-GPS
USB
  • microUSB 2.0
  • USB On-The-Go
  • microUSB 2.0
Bluetooth
  • 5.0
  • A2DP
  • LE
  • 4.0
  • A2DP
Music and Audio
Music and Audio — specifications for X21 UD, Boost MAX+.
SpecificationX21 UDBoost MAX+
Radio
  • FM radio
  • No
Others
  • 32-bit/192kHz audio -Active noise cancellation with dedicated mic
  • Dolby Digital Plus audio enhancement audio -Active noise cancellation with dedicated mic
Other features
Other features — specifications for X21 UD, Boost MAX+.
SpecificationX21 UDBoost MAX+
Dop
  • Sensors Fingerprint (under display)
  • accelerometer
  • proximity
  • compass - Fast battery charging
  • Sensors Yes