The Distance Learning Team of TU Wien recommends the tool "Termino" (weblink) for the administration and coordination of calendar events and appointments with internal and external persons. The tool "Calendly" is not serviced by TU Wien, which means that no support can be given.
Calendar in which 'timeslots' can be specified (e.g. in 15-minute intervals), which are then reserved by other users (e.g. students). In this way, the planning of office hours is greatly facilitated.