J'ai l'impression qu'il s'agit d'une fonction permettant de chercher ("sonder") les dates de rendez-vous possibles selon les disponibilités de chacun.

D'après le site suivant :

Create appointment poll
Start the appointment poll to find the perfect time for your meetings etc. An assistant will guide you through the process and helps you to configure your poll and to integrate special features like one or more casual poll(s) and a messageboard.
http://www.planiteasy.de/en/2307d0988400a3d20/index.html

Looking for an appointment? Find appointments for groups (and organize it)!
1. Create appointment with title, description and proposals for possible dates. You can also integrate a poll and a messageboard.

2. Send the created link to your participants or let it send automatically by plan|it|easy.

3. With this link the participant gets access to the appointment-poll and can vote for the date of his choice, possibly vote on the poll and leave messages on the messageboard.
http://www.planiteasy.de/en/03c19898cd0f49902/index.php