A couple of months ago, Microsoft added the functionality to transfer contextual information from a host Team or channel into a Power App. This is a big improvement for citizen developers who are developing apps to be consumed in a Microsoft Teams context. Apps can now be created with an upfront knowledge of where the app is hosted, the size of the app, client type, theme, and more. For a full list of parameters, you can read my article on creating Teams-aware Power Apps. Once an app is built, it can be exported from the maker portal and imported into Teams to be consumed by users.