I do no think there is a direct solution but it can be easly developed. For example, for the Veterinarian Vertical we’ve used the folllowing aproach:
We use the Scheduled, Waiting and In progress states for appointments with the following means:
Scheduled: The appointment is scheduled but the person has not arrieved to the waiting room yet
Waiting: The person has arrieved and it’s waiting.
In-Progress: The person leaved the waiting room and started the appointment.
With this structure its easy to develop a web panell that pulls the information from tryton, to list the last appoinment that entered, and the ones that are waiting. Of course, each appointment has an unique number that can be used for the customer to identify it’s own turn.
Hope it helps!