Smaller screens: The usable area is 150 by 150 pixels only on a typical Palm OS device, and not a whole lot larger (177 by 208 pixels) on a Nokia 3650 smart phone or a typical Pocket PC device (215 by 270 pixels). A desktop PC screen is typically in the neighborhood of 1024 by 768 pixels. Large graphics and wide tables are out. See Designing pages for the channel Web site and Designing graphics for channel pages.

Big differences in platforms: The hardware differences between various mobile devices are much greater than the differences you are used to dealing with between IE vs. Netscape, or PC vs. Mac. This makes it much harder to use a lowest common denominator approach, in which a single set of Web pages with a fixed standard for graphics will look OK on all platforms. See Customizing Content for Users and Devices.

Limited memory: Some users will turn off graphics to get more content onto their devices and users may remove your channel if it takes up too much memory on a device. See Designing the channel Web site.