Simplest way to get a full set of favicons and touch icons
If you use the metatag module you can use the -favicon and -mobile submodules.

If you visit admin/config/search/metatags (Configuration > Search and Metadata > Metatags), you can alter a metatag set. And you'll get this section:



Here you can enter the paths to the files relative to your Drupal root. eg. sites/default/files/metatags/favicon.ico. Depending on where you've uploaded these files. (You need FTP for this.)

The -mobile submodule will add MS Application icons and in another section.