We used Zoom for remote classes over the summer but at this point, I've also used Coding Rooms, Big Blue Button, and Google meet as well. They each have their own strong points and failings but all are limited in terms of sharing multiple cameras and screen components. All will let you share your camera or share your screen and when you share you screen you can either share it all or a single window. Zoom is the only one that seems to allow for easy camera switching but it's still pretty clunky.
Why do I want to switch cameras? Because I can't draw us ing a mouse or touchpad. I've gotten myself a Wacom tablet but am still not particularly proficient at it.
So, I got myself one of these to use as a document camera. It worked but as I said, switching between the webcam and document camera was clunky at best.
OBS to the rescue!!!!!
OBS Studio is the Open Broadcaster Software. It's a cross platform streaming studio. You can set up any number of devices and then compose them into scenes. I use it for recording my Emacs videos. It's easy to set up devices for every camera you own plus monitors and individual windows. It only took a minute or so to set up a scene with me in the corner and my desktop:
One for my document camera:
And one for my desktop with the doccam overlayed.
I can switch between them by clicking on which I want. I can also select a transition like fade.
This is all great for recording or streaming to a service like Twitch but what about using with meeting software? It turns out that you can set up OBS to act as a virtual camera. There are plugins for Mac and Windows. You can find them by searching for them but for Linux, I followed this video and it worked perfectly:
I also found this video if the above one doesn't work: https://www.youtube.com/watch?v=zaJSkj-dLoI
I set up the virtual camera as per the video and then selected it as the camera on both Zoom and Coding Rooms and it worked perfectly. It should work on the other platforms as well.
This is HUGE. Now, instead of explicitly sharing my screen I can hacve my screen as my image and quickly and easily switch over to another window, a document camera or anything else.
If you're teaching remotely using a conferencing platform I recommend you check this out.