I want to design an app that will allow a user, to collaborate with another user from his/her contact list.
It basically allows two users to track a balance of expenses between them.
I don’t understand how a user can see who else from his contact list uses the app. If the other contact does not have the app - a link should be sent. If the app is installed then the session can start.
Then once a user selects the other user to create a session, how those two are interacting, probably with a sheet of their own.
If there is available template which demonstrates that concept, it will be of great help.
Also, if there are specific videos as a reference, it will also be great.