Many of today’s mobile devices use a touch screen interface. A few examples include: Apple’s iPod Touch, iTouch, iPhone, and iPad. The same is true for Google’s Android and several Blackberry models. It’s important to design websites with these devices in mind.
Most mobile devices also have functionality limitations, usually designed to extend battery life, or improve user experience with limited bandwidth. The Apple devices don’t natively support Flash. Although there are apps that enable Flash playing, its best to minimize the use of Flash in a new site build. And Flash should be completely avoided when designing a mobile-specific website. Likewise, it’s a good idea to use fewer images. Keeping the site light will greatly improve the user’s experience by reducing download time. Keep in mind, mobile devices have limited bandwidth.
For touch interfacing, navigation menus must be also considered. Many website designs incorporate drop-down menus that are triggered with hovering of the mouse. However, you can’t hover with a touch interface. There are several work-arounds, including clickable (touchable) drop-down menus, or scrolling menus. But it may just be easiest to avoid drop-down menuing all together. Minimizing the use of complicated drop-down navigation seems to be a trend anyway. Probably in part because it’s problematic on mobile devices, and partly due to the natural streamlining of design. Simpler is better.