Mobile Safari requires the use of the following incantation for favicons of a higher resolution than the traditional 16x16:
<link rel="shortcut icon" href="old-16x16-favicon.ico" />
<link rel="apple-touch-icon" sizes="158x158" href="my-new-158x158-icon.png" />
However, Firefox requires the use of the HTML5 syntax, e.g.:
<link rel="shortcut icon" href="old-16x16-favicon.ico" />
<link rel="icon" type="image/png" sizes="158x158" href="my-new-158x158-icon.png" />
Now, my expectation is that it should be possible to combine these into a single line, as follows.
<link rel="shortcut icon" href="old-16x16-favicon.ico" />
<link rel="icon apple-touch-icon" type="image/png" sizes="158x158" href="my-new-158x158-icon.png" />
Does anyone know of any problems with this? We all know things are rarely this simple, and I don't have an iOS device to test against, let alone all the other devices out there that have no-doubt copied the Apple syntax.