Good point! Just revised it!
Are you using row owners?
Yes, each chat’s users are now row owners—I had to build a combination of formulas in the spreadsheet to make this happen. @Mark, it would be nice to allow Split Column to be a row owner column to avoid this.
When a person leaves the chat is there a way for the app owner to find out that the person did actual participate in that chat ?
Yes, the “invited users” column will always include all users that ever participated in the chat.
Do you use anonymous emails in the chat?
This can be enabled in settings with no adverse effects. I had it disabled for the sake of the promo video.
Can the app owner owner delete a user all together and then remove all his/her comments in the app?
Yes, as the app owner, you can remove the user and all comments from the Privacy menu in the App Settings.
Thanks for the reminders and recommendations, @Krivo and for the genius idea of stacked floating buttons. It was a lot of fun to design!