Bridgy - Bridgy pulls comments, likes, and reshares on social networks back to your web site. You can also use it to post to social networks - or comment, like, reshare, or even RSVP - from your own web site. https://brid.gy/

CodeRevolution - Automatic posting to different social networks using WordPress plugins.

SkyStats - An all-in-one WordPress dashboard plugin brings analytics, social media, paid search, email, video and marketing metrics into a single customizable view.

Blog2Social - Auto post, cross post, re publish, re post and schedule your WordPress blogs posts to social networks like Facebook, Twitter, LinkedIn, Instagram, Pinterest

Webmention.io - Webmention.io is a hosted service created to easily receive webmentions on any web page.

Friendica - Decentralisation - Privacy - Interoperability