All ways to specify an iOS springboard icon for a website

As per some google search results, this for example, there are at least two ways to specify an iOS springboard icon f开发者_StackOverflowor a website (home screen favicon):

• Create a PNG image that is 57×57 pixels in size and save it as “apple-touch-icon.png” in the root of the website.
• Specify any image as the icon using html <link> tag like this: <link rel="apple-touch-icon" href="/whatever.jpg"/>

Yahoo's mobile site, http://m.yahoo.com/, does display a favicon on my iphone. However, m.yahoo.com/apple-touch-icon.png is not available, and there is not such a <link> in its html source.

So are there any other ways to specify that icon?

Here is a good reference on the topic
http://mathiasbynens.be/notes/touch-icons