Why am I getting error for apple-touch-icon-precomposed.png
Solution 1:
I guess apple devices make those requests if the device owner adds the site to it. This is the equivalent of the favicon. To resolve, add 2 100×100 png files, save it as apple-touch-icon-precomposed.png and apple-touch-icon.png and upload it to the root directory of the server. After that, the error should be gone.
I noticed lots of requests for apple-touch-icon-precomposed.png and apple-touch-icon.png in the logs that tried to load the images from the root directory of the site. I first thought it was a misconfiguration of the mobile theme and plugin, but found out later that Apple devices make those requests if the device owner adds the site to it.
Source: Why Webmasters Should Analyze Their 404 Error Log (Mar 2012; by Martin Brinkmann)
Solution 2:
If a user from Safari Web browser (Apple devices) visit your site. The browser tries to fetch the site icon if it is not defined in <head> in the following order:
- apple-touch-icon-57x57-precomposed.png
- apple-touch-icon-57x57.png
- apple-touch-icon-precomposed.png
- apple-touch-icon.png
To resolve this issue either define an icon for safari web browsers or apple devices. Add something like this to head section of your site:
<link rel="apple-touch-icon" href="/custom_icon.png"/>
If you want to keep <head> clean then upload the icon to root dir of your site with proper name.
The default icon size is 57px.
You can find more details on iOS developer library.