[mjn]

I don't believe Colab is real-time live in the way that Google Docs is. I'm using it to teach a class and would love that kind of functionality, but unless I'm missing some option, when I make changes to the notebook, students who have it open don't see the changes immediately, only when they reload.

[lrem]

I haven't tried coding live, but comment threads do seem real-time. Probably wrong assumption on my part, sorry.