We got the below response from engineering team :
Deeplink is the best way to always land the user in a certain app. But if you want the user to open their Teams desktop client and automatically open a certain app, then that is not possible right now. Teams client tries to remember your last state and takes you to that when you open Teams again. If there is no last state, like opening Teams for the first time, then it will open the first app in the left app bar.
One option to explore will be to send proactive notification from a bot in case they want to inform the users about something.
Thanks,
Meghana
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