TeamCal Neo is the official successor of the popular TeamCal Pro. It is a web-based calendar application written in PHP and MySQL. It's purpose is the day-based absence management of project teams.
TeamCal Neo's goal was to keep the successful concept of a day-based calendar while modernizing the code-base and improving the UX with a responsive design. You can view it conveniently on any mobile device due to its responsive web design.
TeamCal Neo supports the customization of holiday types and absence types, thus, its purpose can be altered to any graphical representation of timeline based processes or activities, e.g. a simple project plan or an event management. I have seen many great ideas of how to use TeamCal Pro that can also be done in TeamCal Neo.