Google+ platform websites integration using the Google+ platform tag.
AddThis, the new brand name for Clearspring Technologies, is the leader in socially connecting publishers, services and advertisers to audiences on the open web. Reaching more than 1.3 billion unique users monthly, AddThis’ social tools and analytics are used on more than 14 million unique domains to distribute and track digital...
Open graph description entity tag
Chrome for Android, since version 39 supports the "theme-color" meta tag to allow websites control the background color of the tab's UI header.
Indicates that the site provides an interface specifically for searching the document and its related resources.