I wrote a blog this week how it is possible to create a Power App that can be added to a Teams meeting AND it "knows" that it is connected a meeting. In short: those Apps can contain information about something related to that specific meeting and they are also "aware" when the application is opened inside the meeting as a side panel or is it opened as a tab in the pre/post-meeting screen.
If you are interested please do read more from my post:
https://myteamsday.com/2021/03/10/meeting-aware-powerapp/
For this "meeting awareness/connection" the PowerApp needs to be a Dataverse for Teams application.
Earlier I had blogged how to create PowerApps that can be added to a meeting. It explains steps needed to alter the PowerApp manifest https://myteamsday.com/2021/01/13/create-meeting-apps/
