Apple Icon: This property determines the Apple icon. Images must be square .PNG files, at least 76 x 76 pixels in size.
Google Site Verification: This Google Webmaster Tools-specific meta tag is used on the top-level page of the site to verify the ownership of a site within webmaster tools. This property will set the 'google-site-verification' content tag.
Facebook domain verification: This property defines and ID that is used to verify domain ownership to Facebook. This property will set the ‘facebook-domain-verification’ content tag.
Bing Verification: This property defines the ID that is used to verify ownership to Bing.
Bitly Verification: This property defines the ID that is used to verify ownership to Bitly.
Yahoo Verification: This property defines the ID that is used to verify ownership to Yahoo.
Pinterest Verification: This property defines the ID that is used to verify ownership to Pinterest.
Apple Native App ID: If the site has an associated Apple native app, the ID will add a small promotion for the app whenever a user visits the site in mobile Safari browser.
Android Native App ID: If the site has an associated Android native app, the ID will add a small promotion for the app whenever a user visits the site in mobile device.