Google Analytics is a free web analytics service that tracks and reports website traffic.
Mailchimp is a marketing automation platform and email marketing service.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
Open Graph is a protocol that is used to integrate any web page into the social graph.
The SEO Framework is the only WordPress plugin that can intelligently generate critical SEO meta tags by reading your WordPress environment.