One of the biggest differences between Arcol and existing modelling tools is that multiple people can be working in a project at the same time and see any changes being made right when they happen.
You’ll know who is working alongside you because their avatar will show in the top right of the project page and you’ll see their cursor moving around in the file. If a teammate selects an element in the model or on a board you’ll see the element selected as the teammate’s color.