Justin discovered that epic, which was already in use across the company, had just such a solution!
Although the epic chat-room does not involve video or audio (chats are typed) staff liked the fact that it was simple to set up, used minimal data, and was mobile App enabled.
A surprising factor that makes it all the more popular for those working from home is that it doesn't matter what you look like or what noise (dogs, kids, etc.) is going on in the background because nobody can see or hear you anyway.
In fact, you can move around the house, using the chat room on the mobile app, while still being fully engaged in the meeting – and nobody in the chat room is any the wiser!