Different examples of mob environments exist, for example, Hunter Industries uses an open office environment, where each mob has its own area with desks facing several large hi-res screens, surrounded by whiteboards.
There is one computer with one keyboard, the team member who sits at the keyboard is known as the driver. The other members of the team are known as the navigators. There is room for others to sit at the desk, including the team coach.
For the mob to switch out drivers quickly, it's probably wise to be familiar with one IDE and set of tools. Although it's not impossible to have more than one IDE set up on a computer, there are benefits from everyone in the team using the same environment, knowledge ...
