| 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. |
| FirebaseNetworkException | Exception thrown when a request to a Firebase service has failed due to a network error. |
| FirebaseTooManyRequestsException | Exception thrown when a request to a Firebase service has been blocked due to having received too many consecutive requests from the same device. |