Plastic (Polycarbonate or TPU): Lightweight and flexible, often used for budget and mid-range devices.

• Metal (Aluminum/Alloy): Premium look, better heat dissipation, commonly used in high-end devices.
• Glass: Offers a modern design, supports wireless charging but is more fragile.
• Leather or Vegan Leather: Used in luxury or flagship phones for a premium feel.

3. Features:

• Cutouts for camera, fingerprint sensor, charging port, speaker, and buttons.
• In some cases, includes antenna lines for better signal reception.
• May integrate wireless charging coils (in glass backshells).
• Comes in various finishes: matte, glossy, textured, etc.

4. Types:

• Integrated Backshell: Part of the phone’s unibody design, not meant to be removed by the user.
• Removable Backshell: Can be detached to access battery, SIM, or SD card slot (common in older models).