Over the years I've created a few different versions of In/Out boards like this that have used Exchange FreeBusy information to present the In/Out status for Users. In this post I am going to look at how you can create the same thing in Microsoft Teams using a Team's tab application that will call some Microsoft Graph endpoints that will first get the members of a particular Team, then there OOF MailTip to determine if they have an AutoResponse set and finally get there userphoto. The end results is a board that looks like this Team's Tab Applications Team's tab apps are very simular to the Add in's framework used across other Office365 products that utilize JavaScript and html to provide a consistent approach across desktop and web clients. However because teams is fairly new the underlying client SDK isn't as feature rich or mature as you would find for example with Exchange/Outlook. Some examples of this is there is no way to get the members of a Team
Pushing the Envelope in Messaging and Office 365 Development