Add these lines of code to your header (of cause needs image files too)
This makes it open up as if it's a native app and changes the status bar from white to see through.
<meta name="apple-mobile-web-app-capable" content="yes" />
<meta name="apple-mobile-web-app-status-bar-style" content="black" />
This adds a startup image (needs to be 460 not 480 like normal) and icon when saved to springboard (delete the precomposed if you need the iphone to round and shine it as that is for icons already made completely as they should be on springboard.)
<link rel="apple-touch-icon-precomposed" href="icon.png"/>
<link rel="apple-touch-startup-image" href="hacker.png"/>