Category: Techie

I just came across this neat trick for providing custom icons (think favicon.ico, but with a reasonable size, better colour and a proper file format) for web pages for iPhone/iPod touch users. There seemed to be some debate over what exactly the native size is, so I built a test page to test it. The full-size icon image is also displayed on the page, but that’s only there to show what the phone is starting with.
After twiddling with this test for a while, I came to the conclusion that there isn’t a native size – it’s somewhere between 59×59 and 60×60 – though 60×60 is about as close as you can get. This lack of native size is interesting, as it implies that the iPhone UI is using resolution independent rendering, which we know OS X can do.
Bigger sizes do scale more smoothly, but they’re a waste of bandwidth and mean that you lose control of the exact appearance – photographic icons will look very nice, but anything involving single pixels lines will probably suffer badly. If you’re a pixel geek that doesn’t like your images twiddled with and you’ve painstakingly created your icon in Photoshop, you need to know the native size. If anyone finds a perfect image size (which may well not be square), please leave a comment.