Most of the social networking sites like Facebook etc show a list of online friends. By default BuddyPress doesn’t provides you the feature that each member in your BuddyPress network can see the list of his online friends after logging in to his account.
You can add a widget showing online friend list to your members in your BuddyPress powered network. You can do it either by hack or by using a plugin. Here we will be discussing about plugin because it more easy to use. If you like adding using hack then follow this post.
Install and activate BP Show Friends plugin. Visit your Dashboard -> Appearance -> Widgets and drag BP Show Friends Widget to your sidebar, as shown in the following image:
It displays the friends of the logged in user or of the displayed user once in BuddyPress Member area.