User Activity is a tool for tracking user activity in the Joomla! CMS, and is released under the General Public License 2 or newer. For more information about Joomla!, please visit: http://www.joomla.org/about-joomla.html
Downloads and updates are available on projectfork.net (which is my main project): https://projectfork.net/downloads/user-activity
The documentation for end-users can be found here: https://projectfork.net/docs/23-user-activity/45-introduction
Developers please visit the github wiki, here: https://github.com/eaxs/User-Activity/wiki