T-Mobile Sidekick vs ZTE X990

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.

  • Weight

    X990: 38 g lighter

    Sidekick:
    128 g
    X990:
    90 g
  • Width

    Sidekick: 3 mm narrower

    Sidekick:
    58 mm
    X990:
    61 mm
  • Depth

    X990: 6 mm thinner

    Sidekick:
    18 mm
    X990:
    12 mm
  • Height

    X990: 12 mm shorter

    Sidekick:
    119 mm
    X990:
    107 mm
  • Release year

    Sidekick:
    2008
    X990:
    2010

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. Sidekick

    Height:
    119 mm +12 mm versus X990
    Width:
    58 mm
    Depth:
    18 mm +6 mm versus X990
  2. 2. X990

    Height:
    107 mm
    Width:
    61 mm +3 mm versus Sidekick
    Depth:
    12 mm

Weight

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

  1. 1. Sidekick

    128 g

    +38 g versus X990

  2. 2. X990

    90 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. Sidekick

    Screen diagonal:
    2.6 in
    Aspect ratio (height:width):
    5:3
    Approximate rectangular screen area:
    19.2 cm²
  2. 2. X990

    Screen diagonal:
    2.5 in
    Aspect ratio (height:width):
    4:3
    Approximate rectangular screen area:
    19.4 cm²

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.

No unambiguous storage/RAM pairings are recorded. See the original specifications below.

Sidekick: Original memory entry

128 MB RAM · 64 MB ROM

X990: Original memory entry

5 MB

Practical features

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

1. Sidekick

NFC:
Unknown
Headphone jack:
Yes
Memory card support:
See details microSD (dedicated slot)

2. X990

NFC:
Unknown
Headphone jack:
No
Memory card support:
See details microSD · up to 8 GB (dedicated slot)

Battery capacity

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

At least two unambiguous positive capacity values are needed for a chart. Original entries remain in the specifications.

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. Sidekick2. X990

Everyday essentials
Everyday essentials — specifications for Sidekick, X990.
SpecificationSidekickX990
Dimensions (HxWxD)
  • 119 Х 58 Х 18 mm
  • 107 Х 61 Х 12 mm
Weight
  • 128 g
  • 90 g
Technology
  • TFT
  • TFT
Screen size
  • 2.6" inch
  • 2.5" inch
Screen resolution
  • 240 x 400 px
  • 320 x 240 px
Internal memory Recorded storage / RAM variants. Entries are alternatives, not a combined maximum. Ambiguous formats stay as recorded.
  • 128 MB RAM
  • 64 MB ROM
  • 5 MB
Memory card support
  • microSD (dedicated slot)
  • microSD
  • up to 8 GB (dedicated slot)
Battery Capacity is not battery life. No endurance test is implied.
  • 1030 mAh
  • Removable Li-Ion
  • 0 mAh,
Operating system OS
  • Danger 4.7
  • Microsoft Windows Mobile 6.5 Professional
Headphone jack
  • Yes
  • No
Display
Display — specifications for Sidekick, X990.
SpecificationSidekickX990
Touchscreen Unknown
  • resistive touchscreen
Display colors
  • 65K
  • 256K
Screen area
  • 19.2 cm2
  • 19.4 cm2
Screen format
  • 5:3 (height:width)
  • 4:3 (height:width)
Screen to body ratio
  • 27.9%
  • 29.7%
PPI /points per inch/
  • 179 PPI
  • 160 PPI
Camera and Video
Camera and Video — specifications for Sidekick, X990.
SpecificationSidekickX990
Rear camera, main
  • 1.3 MP
  • Single
  • 2 MP
  • Single
Camera specs
  • 1.3 MP
  • 2 MP
Video
  • Yes
  • Yes
Front camera, selfie
  • 0 MP,
  • 0 MP,
General specs
General specs — specifications for Sidekick, X990.
SpecificationSidekickX990
Release date
  • 2008
  • July
  • 2010
  • March
Colors
  • Black
  • White
Battery life
  • Stand by time- Up to 216 h Talking time- Up to 5 h
  • Stand by time- Up to 480 h Talking time- Up to 8 h
Communication and Connectivity
Communication and Connectivity — specifications for Sidekick, X990.
SpecificationSidekickX990
SIM card
  • Mini-SIM
  • Mini-SIM
GPRS
  • Class 10
  • Class 10
Edge
  • Class 10
  • Class 10
Wi-Fi
  • No
  • No
GPS
  • No
  • No
USB
  • miniUSB
  • microUSB 2.0
Bluetooth
  • 2.0
  • A2DP
  • 2.0
  • A2DP
Harmful irradiation Unknown
  • SAR EU - 0.96 W/kg (head)
Music and Audio
Music and Audio — specifications for Sidekick, X990.
SpecificationSidekickX990
Radio
  • No
  • Stereo FM radio
  • RDS
Others
  • Swivel display
Unknown
Other features
Other features — specifications for Sidekick, X990.
SpecificationSidekickX990
Dop
  • MP3/WAV/WMA audio player -MP4 player -Voice memo -Predictive text input
  • Windows Live Messenger -MP3/WMA/eAAC+ player -MP4/H.264 player -MS Office -Organizer -Voice memo -Predictive text input Also known as Messenger by SFR 251 Edition