9hdigital

This plugin will allow users to chat with the website’s business in real-time by using Facebook Messenger. Users can start a conversation on the website and continue it on other devices at any time.
Please note, Facebook is still currently developing their Customer Chat and so it is still in beta.

WP Chat

Chat with business customers on your website using Facebook Messenger

kalkie

This widget shows tweets in real-time that match a given search term. The search term can be changed in the options screen of the widget. Links or Mentions are changes so they become actual links. The tweets show using a smooth scrolling and easing effect. All animation parameters can be changed via the options screen.

Twitter search smooth scrolling

This widget shows tweets in real-time that match a given search term. The search term can be changed in the options screen of the widget.

WP Chat vs Twitter search smooth scrolling