Just to reiterate something very important:
Git/GitHub are great tools that, while they support collaboration, are primarily for version control. Knowing how to use git and/or GitHub effectively is something that all programming projects will benefit from, regardless of the number of people who are working on the project at a given moment. My team has been using github for version control and as a cloud-based solution to guaranteed secure storage of our files. In addition, GitHub has become basically the best tool for sharing open-source projects and making code available to a wider community that can benefit from it. In terms of real-time collaboration however, I highly recommend either VS Code’s Liveshare or Atom Teletype. My team uses Teletype even when we are all on-site to ensure that everyone is working at maximum productivity. It greatly helps us work on many different aspects of code at once. The general workflow for using Teletype for collaboration on code in real time should be as follows: one machine (ideally a laptop or something mobile) should be used as the host machine. Files should be locally stored on this machine and this is the machine that should be used to compile and upload code to the V5 brain. Other machines can then enter a sharing mode on any open files on the host machine. My team generally has only the host work on writing actual code, while the “satellite machines” write code in commented blocks so that whenever the host chooses to compile and upload, the code is not ever in an “unfinished” state. When the “satellites” are ready to add or push changes to the robot, they can uncomment blocks of code.
TLDR: GitHub is a great tool for version control, that I highly recommend for ANY programming project. Atom Teletype or VS Code Liveshare is the way to go for real time collaboration.