Installation & Setup on Apple platforms

The Firebase Realtime Database is a cloud-hosted database. Data is stored as JSON and synchronized in realtime to every connected client. When you build cross-platform apps with our Android, iOS, and JavaScript SDKs, all of your clients share one Realtime Database instance and automatically receive updates with the newest data.

Firebase Realtime Database is available on all Apple platforms, including iOS, macOS, macOS Catalyst, tvOS, and watchOS. It is not available for App Clips. The setup instructions in this page reference iOS in specific examples, but are generic and work for any Apple platform target.

Prerequisites

1. Install the Firebase SDK.
2. Add your app to your Firebase project in the Firebase console.

Create a Database

1. Navigate to the Realtime Database section of the Firebase console. You'll be prompted to select an existing Firebase project. Follow the database creation workflow.

2. Select a starting mode for your Firebase Security Rules:

   Test mode

   Good for getting started with the mobile and web client libraries, but allows anyone to read and overwrite your data. After testing, make sure to review the Understand Firebase Realtime Database Rules section.

   Note: If you create a database in Test mode and make no changes to the default world-readable and world-writeable Rules within a trial period, you will be alerted by email, then your database rules will deny all requests. Note the expiration date during the Firebase console setup flow.

   To get started with the web, Apple, or Android SDK, select testmode.

   Locked mode

   Denies all reads and writes from mobile and web clients. Your authenticated application servers can still access your database.

3. Choose a location for the database.

   Depending on the location of the database, the URL for the new database will be in one of the following forms:

   • DATABASE_NAME.firebaseio.com (for databases in us-central1)

   • DATABASE_NAME.REGION.firebasedatabase.app (for databases in all other locations)

4. Click Done.

When you enable Realtime Database, it also enables the API in the Cloud API Manager.

Add Firebase Realtime Database to your app

Use Swift Package Manager to install and manage Firebase dependencies.

Visit our installation guide to learn about the different ways you can add Firebase SDKs to your Apple project, including importing frameworks directly and using CocoaPods.

1. In Xcode, with your app project open, navigate to File > Add Packages.
2. When prompted, add the Firebase Apple platforms SDK repository:

  https://github.com/firebase/firebase-ios-sdk
  

Note: New projects should use the default (latest) SDK version, but you can choose an older version if needed.
3. Choose the Realtime Database library.
4. When finished, Xcode will automatically begin resolving and downloading your dependencies in the background.

Configure Realtime Database Rules

The Realtime Database provides a declarative rules language that allows you to define how your data should be structured, how it should be indexed, and when your data can be read from and written to.

Note: By default, read and write access to your database is restricted so only authenticated users can read or write data. To get started without setting up Authentication, you can configure your rules for public access. This does make your database open to anyone, even people not using your app, so be sure to restrict your database again when you set up authentication.

Set up Firebase Realtime Database

You must initialize Firebase before any Firebase app reference is created or used. If you have already done this for another Firebase feature, you can skip this step.

1. Import the FirebaseCore module in your UIApplicationDelegate, as well as any other Firebase modules your app delegate uses. For example, to use Cloud Firestore and Authentication:

   Swift

   import FirebaseCore
   import FirebaseFirestore
   import FirebaseAuth
   // ...
         

   Objective-C

   @import FirebaseCore;
   @import FirebaseFirestore;
   @import FirebaseAuth;
   // ...
         

2. Configure a FirebaseApp shared instance, typically in your app's application:didFinishLaunchingWithOptions: method:

   Swift

   // Use Firebase library to configure APIs
   FirebaseApp.configure()

   Objective-C

   // Use Firebase library to configure APIs
   [FIRApp configure];

3. Create a reference to your database and specify the location you want to write to.
   Important: To get a reference to a database other than a us-central1 default database, you must pass the database URL to database() (or for Objective-C databaseWithURL). For a us-central1 default database, you can call database() (or database) without arguments.

   You can find your Realtime Database URL in the Realtime Database section of the Firebase console. Depending on the location of the database, the database URL will be in one of the following forms:

   • https://DATABASE_NAME.firebaseio.com (for databases in us-central1)
   • https://DATABASE_NAME.REGION.firebasedatabase.app (for databases in all other locations)

   Swift

   Note: This Firebase product is not available on the App Clip target.

   var ref: DatabaseReference!
   
   ref = Database.database().reference()

   Objective-C

   Note: This Firebase product is not available on the App Clip target.

   @property (strong, nonatomic) FIRDatabaseReference *ref;
   
   self.ref = [[FIRDatabase database] reference];

Next Steps

• Learn how to structure data for Realtime Database.

• Scale your data across multiple database instances.

• Read and write data.

• View your database in the Firebase console.

• Prepare to launch your app:

  • Enable App Check to help ensure that only your apps can access your databases.

  • Set up budget alerts for your project in the Google Cloud Console.

  • Monitor the Usage and billing dashboard in the Firebase console to get an overall picture of your project's usage across multiple Firebase services. You can also visit the Realtime Database Usage dashboard for more detailed usage information.

  • Review the Firebase launch checklist.