Rolisteam is free virtual tabletop software (under GPLv2). For more details about the project: www.rolisteam.org If you want to read the licence: https://github.com/Rolisteam/rolisteam/blob/master/COPYING.txt
Rolisteam helps you to manage tabletop role playing games with remote friends/players. It provides many features to share maps, pictures and it also includes tool to communicate with your friends/players. The goal is to make Rolisteam-managed RPG games as good as RPG games around your table. To achieve it, we are working hard to provide you more and more features.