Mark has a number of interesting comments on using ICEfaces on mobile devices. One that particularly draws my attention is
Pretty much every input component could be made to simplify its rendering, visually, while not actively being used to input data. This is something that really would not be possible without Ajax.
To some extent, Ajax is not necessary for building a dynamically changing user interface. DHTML techniques alone are sufficient to build a page with controls that spring to full functionality when clicked on. However, when the page is complex, and the configuration of the controls is context sensitive (such as, don't show the user an address form when you have their address in the database) you can see that Ajax really is necessary.
Of course, building a simple user interface isn't only a consideration for mobile devices. We're constantly faced with web sites that prompt for redundant information and are generally difficult to use. Just like the one button mouse forced the MacOS interface to be simplified (remember the three different scrolling behaviors applied by the three mouse buttons in xterm?), we'll see improvements to web pages generally as designers work to accommodate the iPhone.
