The plugin records users who viewed profiles recently
Based on your settings, a user can see who viewed their profile
You can show the most popular users on your site over a period of time. For example, you can list top 10 users on your BuddyPress site over last 30 days(or 7 days etc)
You can also turn on/off the plugin(using code) for users based on roles. For example, you may charge users (Using any of the subscription plugin) and based on their status, you can use a small snnipet of code to show/hide the recent visitors.
The plugin comes with widget for most popular BuddyPress users as well as shortcodes for listing the most popular users on BuddyPress site, recently visiting user for a given user(or logged in)
The plugin also lists the most recent visitors of a user on his profile, in the members directory( a new tab) and if enabled, with a new component on profile(where user can see who visited them in last 7 days, 30 days and all time).