The differences between devices can be split into the following categories:
- Size of the display field
- Input method
- Markup language
- Browser variant
Even if you use the standardized language WML, the differences are so great that you need to create different formatting for the page for different devices, to optimize display. The following sections list the differences in more detail:
Categories
- Size of the display field
- PDA or Smartphone – for example Psion or Nokia 9110 (180 x 400 Pixel)
- PDA or Smartphone with VGA/4 format – such as pocket PC, PalmPilots (similar to VGA/4)
- Small-screen telephones – such as the Nokia 7110, Siemens x35, or Motorola
- Keyboard – for example Psion, Nokia 9110
- On-screen input using keyboard or handwriting recognition – for example, pocket PC, PalmPilot, R380
- Telephone keypad – such as the Nokia 7110, Siemens x35, or Motorola
- HTML 3.2 – for example, pocket PC
- Restricted version of HTML – for example, PalmPilot, i-mode, Mobile Explorer
- WML (version 1.1 or later), such as Nokia 7110, Siemens x35, Motorola
- WAP 1.0
- WAP 1,2
- WAP 1.1 – Nokia
- WAP 1.1 – Openwave Browser
- WAP 1.1 – Ericsson
- WAP browser on PDAs (EZOS, Materna, WAPMan, and so on)

The differences in the display of an Internet service depend not only on the browser variant. The same browser on different devices displays the Internet service differently.
Other differences
- Color display capability (color, grayscale, black and white)
- Graphic formats
See also: