Currently, I am in the process of developing a webpage specifically for the iPhone Facebook app wall link. Interestingly, when attempting to apply the margin attribute to a div within the webpage, the margin doesn't seem to have any effect when clicking on the wall link. However, upon viewing the same page using the Safari browser on an iPhone, the margin does take effect as expected. This discrepancy appears to be related to some form of caching by Facebook of the CSS file. For instance, changes made to the background color in the CSS file are reflected everywhere except within the Facebook web browser on the iPhone app.