Timestamp A Timestamp represents a point in time independent of any time zone or calendar, represented as seconds and fractions of seconds at nanosecond resolution in UTC Epoch time. 
FirebaseApp The entry point of Firebase SDKs. 
FirebaseOptions Configurable Firebase options. 
FirebaseOptions.Builder Builder for constructing FirebaseOptions. 


FirebaseApiNotAvailableException Indicates that a requested API is not available. 
FirebaseException Base class for all Firebase exceptions.