Google APIs are application programming interfaces developed by Google which allow communication with Google Services and their integration to other services.
Using this tag you can set up your web app to have an application shortcut icon added to a device's homescreen, and have the app launch in full-screen "app mode".
CloudFlare is a global CDN and DNS provider that can speed up and protect any site online.
UTF-8 (8-bit UCS/Unicode Transformation Format) is a variable-length character encoding for Unicode. It is the preferred encoding for web pages.
Google's hosted library for web fonts. Allows websites to choose and use fonts from a free, wide variety of fonts.