Surprised all icons is only:
<!-- Icon in the highest resolution we need it for --> <link rel="icon" sizes="192x192" href="/path/to/icon.png">
<!-- Apple Touch Icon (reuse 192px icon.png) --> <link rel="apple-touch-icon" href="/path/to/apple-touch-icon.png">
I thought there was literally like a dozen different sizes and names to support all different Apple and Android devices.