I need to finish a transportation application developed with MIT App Inventor and Firebase. The app is designed to improve a transportation service provided by a small fleet in a small town, which is why these tools are used. The application consists of 5 screens: Home, Registration, Passenger, Driver, and Central. The app must allow user registration with roles of driver, passenger, and coordinator. Drivers should be allowed to accept up to 15 requests simultaneously to start trips. The Central screen is for the coordinator, and on this screen, it should display the following lists: pending drivers, available drivers, busy drivers, as well as options to activate and deactivate drivers. The Home, Registration, Passenger, and Driver screens are functional; only the Central screen is pending.