Any chance you can link the first one (video chat over gameplay)? I'm working on something similar. I've tried searching and didn't turn up all that much.
I was thinking something about Yahoo used to do: a chat room with several types of games and you and your friend could play one of those games while trash talk to each other on video
https://news.ycombinator.com/item?id=22790728
https://rootshirechess.glitch.me/ (https://glitch.com/edit/#!/rootshirechess)