No one else type in the app knows about Firebase. User Interface The app presents a TabView with a UserView tabItem to manage user account and several Rows tabItem. Rows and complementary Row are generic types that allow reuse the same code for diferents Stuffs. GenericHelper GenericHelper is a protocol for conforming type to specialise the generic types. The conforming types Appointment, Note and Task are used to demonstrate private data accessible just by the owner. The conforming type Message is used to demonstrate private data updated just by the owner, but publicly read.