With a custom 57 x 57 icons you can make your site look like an app when a user saves the bookmark to homepage on a iPhone or iPad. It is really easy to do, you just need to add one of code and upload the custom icon. There are free template files you can download and then upload them to your server. You can download the icons for illustrator and photoshop here: http://www.thexyz.com/forum/viewtopic.php?f=97&t=1843 You just need to add your logo to it, save as png and upload to your server. Add the line of code to your index page and then when a user on iPhone or iPad bookmarks your site they will have a branded icon.
Yep I just made this.... tweakshare.info my first wordpress iPhone app your PNG goes in the header and should look like this <link rel="apple-touch-icon" href="/images/tweakshareios.png"/> You can also do conditional statements so it only shows when its loaded on the iPhone and not on the desktop