Firebase FAQ

What is a Firebase project?

A Firebase project is the top-level entity for Firebase. In a project, you can register your Apple, Android, or web apps. After you register your apps with Firebase, you can add the product-specific Firebase SDKs to your app, like Analytics, Cloud Firestore, Crashlytics, or Remote Config.

You should register your Apple, Android, and web app variants within a single Firebase project. You can use multiple Firebase projects to support multiple environments, such as development, staging, and production.

Here are some resources for learning more about Firebase projects:

• Understand Firebase projects — provides brief overviews of several important concepts about Firebase projects, including their relationship with Google Cloud and the basic hierarchy of a project and its apps and resources.
• General best practices for setting up Firebase projects — provides general, high-level best practices for setting up Firebase projects and registering your apps with a project so that you have a clear development workflow that uses distinct environments.

Note that for all Firebase projects, Firebase automatically adds a label of firebase:enabled within the Labels page for your project in the Google Cloud console. Learn more about this label in our FAQ.

What is a Google Cloud organization?

A Google Cloud organization is a container for Google Cloud projects (including Firebase projects). This hierarchy enables better organization, access management, and auditing of your Google Cloud and Firebase projects. For more information, refer to Creating and Managing Organizations.

How do I add Firebase to an existing Google Cloud project?

You may have existing Google Cloud projects managed through the Google Cloud console or the Google APIs console.

You can add Firebase to these existing projects using any of the following options:

• Using the Firebase console:
  In the Firebase console landing page, click Add Project, and then select your existing project from the Project name menu.
• Using a programmatic option:
  • Call the Firebase Management REST API endpoint addFirebase.
  • Run the Firebase CLI command firebase projects:addfirebase.
  • Use Terraform.

Why does my Google Cloud project have a label of firebase:enabled?

In the Labels page for your project in the Google Cloud console, you may see a label of firebase:enabled (specifically, a Key of firebase with a Value of enabled).

Firebase automatically added this label because your project is a Firebase project, which means that your project has Firebase-specific configurations and services enabled for it. Learn more about the relationship between Firebase projects and Google Cloud.

We strongly recommend that you don't modify or delete this label. This label is used by Firebase and Google Cloud to list your Firebase projects (for example, using the REST API projects.list endpoint or in menus within the Firebase console).

Be aware that manually adding this label to your list of project labels does NOT enable Firebase-specific configurations and services for your Google Cloud project. To do that, you need to add Firebase via the Firebase console (or, for advanced use cases, via the Firebase Management REST API or the Firebase CLI).

Why isn't my Firebase project showing up in my list of Firebase projects?

This FAQ is applicable if you don't see your Firebase project in the following places:

• In a list of projects that you're viewing within the Firebase console
• In the response from calling the REST API projects.list endpoint
• In the response from running the Firebase CLI command firebase projects:list

Try these troubleshooting steps:

1. First, try accessing your project by visiting the project's URL directly. Use the following format:
   https://console.firebase.google.com/project/PROJECT-ID/overview
2. If you can't access the project or receive permissions errors, check the following:
   • Make sure that you're signed into Firebase using the same Google account that has access to the project. You can sign in and out of the Firebase console via your account avatar in the top-right corner of the console.
   • Check if you can view the project in the Google Cloud console.
   • Make sure that your project has the label firebase:enabled in the Labels page for your project in the Google Cloud console. Firebase and Google Cloud use this label to list your Firebase projects. If you do not see this label but the Firebase Management API is enabled for your project, then manually add the label (specifically, a Key of firebase with a Value of enabled).
   • Make sure that you're assigned one of the basic IAM roles (Owner, Editor, Viewer) or a role that has Firebase-related permissions in it, for example a Firebase predefined role. You can view your role(s) in the IAM page of the Google Cloud console.
   • If your project belongs to a Google Cloud organization, you may require additional permissions to see the project listed in the Firebase console. Contact the person who manages your Google Cloud organization to give you the appropriate role to view the project, for example the Browser role.

If none of the troubleshooting steps above enable you to see your project in a list of Firebase projects, contact Firebase Support.

How many projects can I have per account?

• Spark pricing plan — Your project quota is limited to a small number of projects (usually around 5-10).
• Blaze pricing plan — Your project quota per Cloud Billing account increases substantially as long as your Cloud Billing account is in good standing.

The limit on project quota is rarely a concern for most developers, but if needed, you can request an increase in your project quota.

Note that the complete deletion of a project requires 30 days and counts toward your quota until it is fully deleted.

How many Firebase Apps can I have in a Firebase project?

A Firebase project is a container for Firebase Apps across Apple, Android, and web. Firebase restricts the total number of Firebase Apps within a Firebase project to 30.

After this number, performance starts to degrade (especially for Google Analytics) and eventually, at a higher number of apps, some product functionality stops working. Additionally, if you use Google sign-in as an authentication provider, an underlying OAuth 2.0 client ID is created for each app in your project. There's a limit of around 30 client IDs that can be created within a single project.

You should ensure that all Firebase Apps within a single Firebase project are platform variants of the same application from an end-user perspective. For example, if you develop a white label application, each independently labeled app should have its own Firebase project, but the Apple and Android versions of that label can be in the same project. Read more detailed guidance in our general best practices for setting up Firebase projects.

In the rare case your project requires more than 30 apps, you can request an app limit increase. Your project must be on the Blaze pricing plan to make this request. Visit the Google Cloud console to make your request and have it evaluated. Learn more about quota management in the Google Cloud documentation.

What happens if I tag my project as a "production" environment?

In the Firebase console, you can tag your Firebase projects with their environment type, either as Production or Unspecified (non-prod) environments.

Tagging your project as an environment type has no effect on how your Firebase project works or its features. However, the tagging can help you and your team manage your various Firebase projects for the app lifecycle.

If you tag your project as a production environment, we add a brightly colored Prod tag to the project in the Firebase console, reminding you that any changes could affect your associated production apps. In the future, we might add more features and safeguards for Firebase projects tagged as production environments.

To change the environment type of your Firebase project, go to settings Project settings > General, then in the Your project card under Environment, click edit to change the environment type.

Where can I find the App ID for my Firebase app?

In the Firebase console, go to your settings Project settings. Scroll down to the Your apps card, then click on the desired Firebase App to view the app's information, including its App ID.

Here are some example App ID values:

• Firebase iOS Apps: 1:1234567890:ios:321abc456def7890
• Firebase Android Apps: 1:1234567890:android:321abc456def7890
• Firebase Web Apps: 1:1234567890:web:321abc456def7890

What are the prerequisites for linking Google Play / AdMob / Google Ads / BigQuery to my Firebase project or app?

• For linking your Google Play account, you need the following:
  • Either of the following Firebase roles: Owner or Firebase Admin
    and
  • Either of the following Google Play access levels: account Owner or Admin
• For linking your AdMob app, you need to be both a Firebase project owner and an AdMob administrator.
• For linking your AdWords account, you need to be both a Firebase project owner and an AdWords administrator.
• For linking your BigQuery project, you need to be the Firebase project owner.

What open source notices should I include in my app?

On Apple platforms, the Firebase pod contains a NOTICES file which includes the relevant entries. The Firebase Android SDK contains a helper Activity for showing license information.

How do I assign a project member a role, like the Owner role?

To manage the role(s) assigned to each project member, you must be an Owner of the Firebase project (or be assigned a role with the permission resourcemanager.projects.setIamPolicy).

Here are the places where you can assign and manage roles:

• The Firebase console offers a simplified way to assign roles to project members in the Users and permissions tab of settings > Project settings. In the Firebase console, you can assign any of the basic roles (Owner, Editor, Viewer), the Firebase Admin/Viewer roles, or any of the Firebase predefined product-category roles.
• The Google Cloud console offers an expansive set of tools to assign roles to project members in the IAM page. In the Cloud console, you can also create and manage custom roles, as well as give service accounts access to your project.

  Note that in the Google Cloud console, project members are called principals.

If the Owner of your project can no longer perform the tasks of an Owner (for example, the person left your company) and your project isn't managed via a Google Cloud organization (see next paragraph), you can contact Firebase Support to have a temporary Owner assigned.

Note that if a Firebase project is part of a Google Cloud organization, it may not have an Owner. If you're unable to find an Owner for your Firebase project, contact the person who manages your Google Cloud organization to assign an Owner for the project.

How do I find the Owner of a Firebase project?

You can view project members and their roles in the following places:

• If you have access to the project in the Firebase console, you can view the list of project members, including Owners, in the Users and permissions page of the Firebase console.
• If you do not have access to the project in the Firebase console, check if you have access to the project in the Google Cloud console. You can view the list of project members, including Owners, in the IAM page of the Google Cloud console.

If the Owner of your project can no longer perform the tasks of an Owner (for example, the person left your company) and your project isn't managed via a Google Cloud organization (see next paragraph), you can contact Firebase Support to have a temporary Owner assigned.

Note that if a Firebase project is part of a Google Cloud organization, it may not have an Owner. Instead, the person who manages your Google Cloud organization can perform many tasks that an Owner can do. However, to perform several Owner-specific tasks (like assigning roles or managing Google Analytics properties), the administrator may need to assign themselves the actual Owner role to perform those tasks. If you're unable to find an Owner for your Firebase project, contact the person who manages your Google Cloud organization to assign an Owner for the project.

Why or when should I assign a project member the Owner role?

To ensure proper management of a Firebase project, it must have an Owner. A project's Owner is the person who can perform several important administrative actions (like assigning roles and managing Google Analytics properties), and Firebase Support can only fulfill administrative requests from demonstrated project Owners.

After you set up the Owner(s) for a Firebase project, it's important to keep those assignments up-to-date.

Note that if a Firebase project is part of a Google Cloud organization, the person who manages your Google Cloud organization can perform many tasks that an Owner can do. However, for several Owner-specific tasks (like assigning roles or managing Google Analytics properties), the administrator may need to assign themselves the actual Owner role to perform those tasks.

I don't think that I have a Firebase project, but I got an email about one. How do I access this project?

The email you received should contain a link to open your Firebase project. Clicking the link in the email should open the project in the Firebase console.

If you're not able to open the project in the link, make sure that you're signed into Firebase using the same Google account that received the email about the project. You can sign in and out of the Firebase console via your account avatar in the top-right corner of the console.

Note that if you're the administrator of a Google Cloud organization, you may be notified about changes to Firebase projects inside your organization. However, you may not have sufficient permissions to open the Firebase project. In these cases, the simplest solution is to assign yourself the actual Owner role to open the project and perform the required actions. Learn more about why and when to assign the Owner role.

What are the supported browsers for accessing the Firebase console?

The Firebase console can be accessed from recent versions of popular desktop browsers such as Chrome, Firefox, Safari and Edge. Mobile browsers are currently not fully supported.

I can load the Firebase console, but why can't I find or access my Firebase project?

This FAQ is applicable if you're experiencing either of the following issues:

• The Firebase console returns an error page that says your project may not exist or that you don't have access to the project.
• The Firebase console doesn't display your project even when you enter its project ID or project name in the console's search field.

Try these troubleshooting steps:

1. First, try accessing your project by visiting the project's URL directly. Use the following format:
   https://console.firebase.google.com/project/PROJECT-ID/overview
2. If you still can't access the project or receive permissions errors, check the following:
   • Make sure that you're signed into Firebase using the same Google account that has access to the project. You can sign in and out of the Firebase console via your account avatar in the top-right corner of the console.
   • Make sure that the Firebase Management API is enabled for the project.
   • Make sure that you're assigned one of the basic IAM roles (Owner, Editor, Viewer) or a role that has Firebase-related permissions in it, for example a Firebase predefined role. You can view your role(s) in the IAM page of the Google Cloud console.
   • If your project belongs to a Google Cloud organization, you may require additional permissions to see the project listed in the Firebase console. Contact the person who manages your Google Cloud organization to give you the appropriate role to view the project, for example the Browser role.

If none of the troubleshooting steps above enable you to find or access your project, contact Firebase Support.

Why is the Firebase console not loading for me?

This FAQ is applicable if you're experiencing any of the following issues:

• A page in the Firebase console never finishes loading.
• Data within a page doesn't load as expected.
• You receive browser error messages when loading the Firebase console.

Try these troubleshooting steps:

1. Check the Console row of the Firebase Status Dashboard for any possible service interruptions.
2. Make sure that you're using a supported browser.
3. Try to load the Firebase console in an incognito or private window.
4. Disable all browser extensions.
5. Verify that the network connection is not blocked by ad blocker, antivirus, proxy, firewall, or other software.
6. Try loading the Firebase console using a different network or device.
7. If using Chrome, check the Developer Tools Console for any errors.

If none of the troubleshooting steps above resolve the issue, contact Firebase Support.

How is my Firebase console language determined?

The language setting for the Firebase console is based on the language selected in your Google account settings.

To change your language preference, see Change language.

The Firebase console supports the following languages:

• English
• Brazilian Portuguese
• French
• German
• Indonesian
• Japanese
• Korean
• Russian
• Simplified Chinese
• Spanish
• Traditional Chinese

What roles and permissions does the Firebase console support?

The Firebase console and Google Cloud console use the same underlying roles and permissions. Learn more about roles and permissions in the Firebase IAM documentation.

Firebase supports the fundamental (basic) roles of Owner, Editor, and Viewer:

• A project Owner can add other members to the project, set up integrations (project linking to services like BigQuery or Slack), and has full edit access for the project.
• A project Editor has full edit access for the project.
• A project Viewer has only read access for the project. Note that the Firebase console currently does not hide/disable edit UI controls from project Viewers, but these operations will fail for project members assigned the Viewer role.

Firebase also supports:

• Firebase predefined roles — Curated Firebase-specific roles that enable more granular access control than the basic roles of Owner, Editor, and Viewer.
• Custom roles — Fully customized IAM roles that you create to tailor a set of permissions that meet the specific requirements of your organization.

Which products are paid? Which are no-cost?

Firebase's paid infrastructure products are the Realtime Database, Cloud Storage for Firebase, Cloud Functions, Hosting, Test Lab, and phone authentication. We offer a no-cost tier for all of these features.

Firebase also has many no-cost products: Analytics, Cloud Messaging, the Notifications composer, Remote Config, App Indexing, Dynamic Links, and Crash Reporting. Use of these products is subject only to the product's traffic control policies (e.g. quotas, fair access and other service protections) in all plans, including our no-cost Spark plan. In addition, all Authentication features beyond phone authentication are no-cost.

How do I know which pricing plan is right for me?

Spark pricing plan

Our Spark plan is a great place to develop your app at no cost. You get all the no-cost Firebase features (Analytics, the Notifications composer, Crashlytics, and so on) and generous amounts of our paid infrastructure features. However, if you exceed your Spark plan resources in a calendar month, your app will be shut off for the remainder of that month. In addition, Google Cloud features are not available when using the Spark plan.

Blaze pricing plan

Our Blaze plan is designed for production apps. The Blaze plan also allows you to extend your app with paid Google Cloud features. You pay only for the resources that you consume, allowing you to scale with demand. We strive to make our Blaze plan prices competitive with industry-leading cloud providers.

How can I monitor my usage and billing?

You can track your usage of project resources in the Firebase console on any of the following dashboards:

• Overall project-level Usage and billing dashboard
• Authentication Usage dashboard (specifically for Phone authentication instances)
• Cloud Firestore Usage dashboard
• Cloud Functions Usage dashboard
• Cloud Storage Usage dashboard
• Hosting Usage dashboard
• Realtime Database Usage dashboard

What happened to the Flame pricing plan?

In January 2020, the Flame pricing plan ($25/mo of additional quota) was removed as an option for new sign-ups. Existing plan users were granted a grace period to migrate their projects off the Flame plan. In February 2022, the remaining projects on the Flame pricing plan were downgraded to the Spark pricing plan.
Accordingly,

• Existing Spark and Blaze plan projects and any new projects can no longer switch to or sign up for the Flame plan.
• If you moved an existing Flame plan project to a different pricing plan, the project cannot return to the Flame plan.
• Projects downgraded to the Spark plan can be upgraded to the Blaze plan to resume additional paid services.
• References to the Flame plan have been removed from documentation.

Do you have more questions about the Flame plan retirement? Read some of the additional FAQs below.

Want to learn about the other pricing plans offered by Firebase? Visit our Firebase pricing page! If you'd like to start moving any existing projects to another pricing plan, you can do that in the Firebase console for your project.

Additional FAQs about the Flame plan retirement

How is the no-cost usage in the Blaze plan different from the no-cost usage in the Spark plan?

No-cost usage on the Blaze plan is calculated daily. Usage limits also differ from the Spark plan for Cloud Functions, phone authentication, and Test Lab.

For Cloud Functions, no-cost usage on the Blaze plan is calculated at the Cloud Billing account level, not the project level and has the following limits:

• 2M invocations/month
• 400K GB-seconds/month
• 200K CPU-seconds/month
• 5 GB of networking egress/month

For phone authentication, no-cost usage on the Blaze plan is calculated monthly.

For Test Lab, no-cost usage on the Blaze plan has the following limits:

• 30 physical device minutes/day
• 60 virtual device minutes/day

Does the no-cost usage quota reset when I change from a Spark to a Blaze plan?

No-cost usage from the Spark plan is included in the Blaze plan. No-cost usage does not reset when moving to a Blaze plan.

What is a "simultaneous database connection"?

A simultaneous connection is equivalent to one mobile device, browser tab, or server app connected to the database. Firebase imposes hard limits on the number of simultaneous connections to your app's database. These limits are in place to protect both Firebase and our users from abuse.

The Spark plan limit is 100 and cannot be raised. The Flame and Blaze plans have a limit of 200,000 simultaneous connections per database.

This limit isn't the same as the total number of users of your app, because your users don't all connect at once. If you need more than 200,000 simultaneous connections, please read Scale with Multiple Databases.

What happens if I exceed Spark plan storage or download limits for Realtime Database?

To provide you with a predictable price, the resources available to you in the Spark plans are capped. This means that when you exceed any plan limit in any month, your app will be turned off to prevent any further resource usage and additional charges.

What happens if I exceed Spark plan simultaneous connection limits for Realtime Database?

When your app reaches its concurrency limit on the Spark plan, any subsequent connections will be rejected until some of the existing connections are closed. The app will continue to work for users who are connected.

How does Firebase's integration with Google Cloud work?

Firebase is deeply integrated with Google Cloud. Projects are shared between Firebase and Google Cloud, so projects can have Firebase services and Google Cloud services enabled. You can access the same project from the Firebase console or the Google Cloud console. Specifically:

• Certain Firebase products are backed directly by Google Cloud, such as Cloud Storage for Firebase. The list of products backed by Google Cloud will continue to grow over time.
• Many of your settings, including collaborators and billing information, are shared by Firebase and Google Cloud. Your usage of both Firebase and Google Cloud appears on the same bill.

In addition, when you upgrade to the Blaze plan, you can use any of Google Cloud's world-class Infrastructure-as-a-Service and APIs directly inside your Firebase project, at standard Google Cloud pricing. You can also export data from Google Cloud directly to BigQuery for analysis. To learn more, see Link BigQuery with Firebase.

There are many security-enhancing, latency-improving, and time-saving benefits to using Google Cloud with Firebase (versus other, cloud services that are not co-located). Check out the Google Cloud site for more details.

What happens to my Firebase project if I add or remove billing accounts for that project in the Google Cloud console?

If a Cloud Billing account is added to a project in the Google Cloud console, the same project will automatically be upgraded to the Firebase Blaze plan if that project is currently on the Spark plan.

In contrast, if an existing active Cloud Billing account is removed from a project in the Google Cloud console, that project will be downgraded to the Firebase Spark plan.

Can I upgrade, downgrade, or cancel at any time?

Yes, you can upgrade, downgrade, or cancel at any time. Note that we don't provide prorated refunds for downgrades or cancellations. This means that if you downgrade or cancel before the end of your billing period, you still pay for the remainder of the month.

What kind of support will I receive?

All Firebase apps, including those using no-cost plans, come with email support from Firebase staff during US Pacific business hours. All accounts have unlimited support for billing-related issues, account-related issues, technical (troubleshooting) questions, and incident reports.

Can I cap usage on the Blaze plan?

No, you cannot currently cap your Blaze plan usage. We are evaluating options for supporting caps on Blaze plan usage.

Blaze users can define a budget for their project or account, and receive alerts as their spending approaches those limits. Learn how to set up budget alerts.

What are automated backups? Do you offer hourly backups?

Automated backups are an advanced feature for customers on our Blaze pricing plan that backs up your Firebase Realtime Database data once a day and uploads it to Google Cloud Storage.

We do not offer hourly backups.

Do you offer open-source, nonprofit, or educational discounts?

Our Spark plan can be used by any type of individual or organization, including nonprofits, schools, and open-source projects. Since these plans already include generous quotas, we don't offer any special discounts or plans for open-source, nonprofit, or educational projects.

Do you offer enterprise contracts, pricing, support, or dedicated infrastructure hosting?

Our Blaze plan is suitable for enterprises of all sizes, and our SLA meets or exceeds the industry standard for cloud infrastructure. However, we do not currently offer enterprise contracts, pricing, or support, nor do we offer dedicated infrastructure hosting (that is, on-premises installations) for services like our Realtime Database. We are hard at work adding some of these features.

Do you offer ad-hoc pricing? I only want pay-as-you-go for one or two features.

We offer ad-hoc pricing in the Blaze plan, where you pay only for the features you use.

How do the paid Firebase plans work with Ads? Are there no-cost advertising credits with paid plans?

The Firebase pricing plans are separate from Ads, so there are no advertising credits without cost. As a Firebase developer, you are able to "link" your Ads account to Firebase to support conversion tracking.

All ads campaigns are managed directly in Ads, and Ads billing is managed from the Ads console.

How do I predict how much I will be billed for upload and download operations?

Visit the Firebase Pricing page and use the Blaze plan calculator. The calculator lists all the usage types for Cloud Storage for Firebase.

Use the sliders to input the expected usage of your Storage bucket. The calculator will estimate your monthly bill.

What happens if I exceed Spark plan upload, download or storage limits for Cloud Storage for Firebase?

When you exceed limits for Cloud Storage in a project on the Spark plan, the result depends on the type of limit that you exceed:

• If you exceed the GB stored limit, you will not be able to store any more data in that project unless you remove some of the data stored or upgrade to a plan that provides more storage space, or unlimited storage space.
• If you exceed the GB downloaded limit, your app will not be able to download more data until the next day (starting at midnight, US Pacific Time), unless you upgrade to a plan with less restrictive limits, or with no limits.
• If you exceed the upload or download operations limit, your app will not be able to upload or download more data until the next day (starting at midnight, US Pacific Time), unless you upgrade to a plan with less restrictive limits, or with no limits.

Where can I find information about privacy and security in Firebase?

Check out the page Privacy and Security in Firebase.

Do the Firebase SDKs log any usage/diagnostic information outside of Analytics?

Yes. This is currently iOS-only, but may change in the future. The Firebase Apple platforms SDK includes the FirebaseCoreDiagnostics framework by default. This framework is used by Firebase to collect SDK usage and diagnostics information to help prioritize future product enhancements. FirebaseCoreDiagnostics is optional, so if you would like to opt out of sending Firebase diagnostic logs, you can do so by unlinking the library from your application. You can browse the full source, including logged values, on GitHub

A/B Testing: How many experiments can I create and run?

You are allowed up to 300 experiments per project, which could consist of up to 24 running experiments, with the rest as draft or completed.

A/B Testing: Why can’t I view my experiments after unlinking and re-linking my project to Google Analytics?

Linking to a different Google Analytics property will cause you to lose access to experiments created beforehand. To regain access to a previous experiment, re-link your project to the Google Analytics property that was linked when the experiment was created.

A/B Testing: Why do I receive a "Project not linked to Google Analytics" message when creating a Remote Config experiment?

If you've already linked Firebase and Google Analytics, but still see a message that Google Analytics is not linked, make sure that an Analytics stream exists for all apps in your project. Currently, all apps in a project must be connected to a Google Analytics stream to use A/B Testing.

You can find the list of all active streams on the Google Analytics integration details page within the Firebase console, accessed from settingsProject Settings chevron_right Integrations chevron_right Google Analytics chevron_right Manage.

Creating a Google Analytics stream for any app that does not have one should resolve the issue. There are a few ways to create streams for missing apps:

• If you only have one or two apps missing an associated Google Analytics stream, you can choose one of the following methods to add a Google Analytics stream:
  • Delete and re-add any app without an active stream in the Firebase console.
  • From the Google Analytics console, select Admin, click Data Streams, then click Add stream, add the missing app's details, and click Register app.
• If you have more than a few missing app streams, unlinking and relinking your Google Analytics property is the fastest and most efficient way to create the missing app streams:
  1. From settings Project Settings, select Integrations.
  2. Within the Google Analytics card, click Manage to access Firebase and Google Analytics settings.
  3. Make a note of the Google Analytics Property ID and the Linked Google Analytics account.
  4. Click more_vert More and select Unlink Analytics from this project.
  5. Review the warning that appears (don't worry here; you will relink the same property in the next step), then click Unlink Google Analytics.
     
     When unlinking is complete, you'll be redirected to the Integrations page.
  6. Within the Google Analytics card, click Enable to begin the relinking process.
  7. Select your Analytics account from the Select account list.
  8. Next to Automatically create a new property in this account, click edit Edit and, from the Analytics property list that appears, select your property ID.
     
     A list of all apps in your project appears. Existing stream mappings for each app are listed, and apps that do not have a stream will have one created for them.
  9. Click Enable Google Analytics to relink the property.
  10. Click Finish.

If you still receive an error creating A/B Tests with Remote Config after performing these steps, contact Firebase Support.

AdMob: Can I link my Windows apps to Firebase?

No, Windows apps are not currently supported.

AdMob: Why can't I link my app to AdMob from the Firebase console?

You can link an AdMob app to a Firebase app via the AdMob console. Learn how.

AdMob: What permissions or access do I need to link a Firebase app to an AdMob app?

In order to do this linking, you need the following access:

• AdMob: You need to be an AdMob admin.
• Firebase: You must have the firebase.links.create permission, which is included in the Owner role and the Firebase Admin role.
• Google Analytics: You must have the Edit role or Manage Users role for the property associated with the Firebase project. Learn more.

AdMob: Can multiple users in the same AdMob account link AdMob apps and Firebase apps?

For multi-user AdMob accounts, the user who created the first Firebase link and accepted the Firebase Terms of Service is the only user who can create new links between AdMob apps and Firebase apps.

AdMob: To use AdMob, which SDKs should I use?

To use AdMob, always use the Google Mobile Ads SDK as described in this FAQ. Additionally and optionally, if you want to collect user metrics for AdMob, then include the Firebase SDK for Google Analytics in your app.

• For iOS projects:
  Import the Google Mobile Ads SDK by following the instructions in the AdMob iOS documentation.
• For Android projects:
  Add the dependency for the Google Mobile Ads SDK to your build.gradle file:
  implementation 'com.google.android.gms:play-services-ads:23.1.0'
  
• For C++ projects and Unity projects: Follow the instructions in the respective documentation.

Analytics: Why is Google Analytics a recommended part of using Firebase products?

Google Analytics is a free and unlimited analytics solution that works with Firebase features to deliver powerful insights. It enables you to view event logs in Crashlytics, notification effectiveness in FCM, deep link performance for Dynamic Links, and in-app purchase data from Google Play. It powers advanced audience targeting in Remote Config, Remote Config personalization, and more.

Google Analytics acts as a layer of intelligence in the Firebase console to provide you with more actionable insights about how to develop a high quality app, grow your user base, and earn more money.

To get started, read the documentation.

Analytics: How do I control how my Analytics data is shared with the rest of Firebase?

By default, your Google Analytics data is used to enhance other Firebase and Google features. You can control how your Google Analytics data is shared in your project settings anytime. Learn more about Data sharing settings.

Analytics: How do I update my Analytics property settings?

From the Admin page in your Google Analytics property, you can update your property settings, such as:

• Data sharing settings
• Data retention settings
• Time zone and currency settings

To update your property settings, follow these steps:

1. In the Firebase console, go to your settings > Project settings.
2. Go to the Integrations tab, and then in the Google Analytics card, click Manage or View link.
3. Click the link for your Google Analytics account to open the account and property settings.

Analytics in my iOS app: Can I install Analytics without ad attribution and IDFA collection features?

Yes. See the Configure Data Collection and Usage page for more details.

Analytics: What changed in the Google Analytics section with the October 2021 update?

You can find a summary of these changes in the Firebase Help Center article New Google Analytics 4 functionality in Google Analytics for Firebase.

Analytics: Why don't I see any Analytics data in the Firebase console after unlinking Firebase from Google Analytics?

Analytics data resides within the Google Analytics property — not within the Firebase project. If you delete or unlink the property, then the Analytics data will not be accessible to Firebase and you'll see an empty Analytics dashboard in the Firebase console. Note that since the data still resides in the previously linked property, you can always relink the property to Firebase and see the Analytics data in the Firebase console.

Linking a brand new Google Analytics account (and thus a new Google Analytics property) to your Firebase project will result in an empty Analytics dashboard in the Firebase console. However, if your previously linked property still exists, then you can move the existing data from the old property to the new property.

Analytics: If my Analytics property and its data were deleted, is there any way to get them back?

No. If your property has been deleted, it isn't possible to undelete the property or retrieve the previously collected Analytics data stored in that property.

If you'd like to start using Google Analytics again, you can link either a new property or an existing property to your Firebase project. You can do this linking in either the Firebase console or the Google Analytics UI. Learn more about linking a Google Analytics property to your Firebase project.

Analytics: If my Analytics property was deleted, can I link a new Google Analytics property to my Firebase project and start using Analytics again?

If you'd like to start using Google Analytics again, you can link either a new property or an existing property to your Firebase project. You can do this linking in either the Firebase console or the Google Analytics UI. Learn more about linking a Google Analytics property to your Firebase project.

Note that since all Analytics data is stored in the property (not the Firebase project), the previously collected Analytics data cannot be retrieved.

Analytics: How will Firebase products or integrated Google products be affected by the deletion of my Analytics property?

Several Firebase products rely on the Google Analytics integration. If your Analytics property and its data are deleted, the following will happen if you use the following products:

• Crashlytics — You can no longer see crash-free users, breadcrumb logs, and/or velocity alerts.
• Cloud Messaging and In-App Messaging — You can no longer use targeting, campaign metrics, audience segmentation, and analytics labels.
• Remote Config — You can no longer use targeted configurations or Personalization.
• A/B Testing — You can no longer use A/B Testing since the experiment measurement is supplied by Google Analytics.
• Dynamic Links — Any feature that relies on data from Google Analytics will be disrupted.

In addition, the following integrations will be affected:

• You can no longer export Analytics data to BigQuery.
• You can no longer take advantage of Google Ads integrations or Google AdMob integrations.

Analytics: How do I segment users who have not met some criterion?

You can reframe the problem by "negatively targeting" these users. For example, reframe the problem as "Don't show ads to people who have bought something", and form an audience of those users to target.

Analytics: Are audiences and/or events defined in the Google Analytics interface also available in the Firebase console?

Your audiences and user properties will be synced. For some features, you'll need to use the Google Analytics interface, such as segmentation and closed funnels. You can access the Google Analytics interface directly via deep-links from the Firebase console.

Any changes you make from the Firebase console can also be performed in Google Analytics, and those changes will be reflected in Firebase.

Firebase Authentication: Which countries are supported for phone authentication?

Firebase Authentication supports phone number verification across the the world, but not all networks reliably deliver our verification messages. The following countries have good rates of delivery, and should be expected to work well for phone number sign in.

Cloud Messaging: What's the difference between the Notifications composer and Cloud Messaging?

Firebase Cloud Messaging provides a complete set of messaging capabilities through its client SDKs and HTTP and XMPP server protocols. For deployments with more complex messaging requirements, FCM is the right choice.

The Notifications composer is a lightweight, serverless messaging solution built on Firebase Cloud Messaging. With a user-friendly graphical console and reduced coding requirements, the Notifications composer lets users easily send messages to reengage and retain users, foster app growth, and support marketing campaigns.

Cloud Messaging: Apple announced they're deprecating the legacy binary protocol for APNs. Do I need to do anything?

No. Firebase Cloud Messaging switched to the HTTP/2-based APNs protocol in 2017. If you are using FCM to send notifications to iOS devices, there should be no action required on your part.

Cloud Messaging: Do I need to use other Firebase services in order to use FCM?

You can use Firebase Cloud Messaging as a standalone component, in the same manner as you did with GCM, without using other Firebase services.

Cloud Messaging: I am an existing Google Cloud Messaging (GCM) developer. Should I move to Firebase Cloud Messaging?

FCM is the new version of GCM under the Firebase brand. It inherits GCM’s core infrastructure, with new SDKs to make Cloud Messaging development easier.

Benefits of upgrading to FCM SDK include:

• Simpler client development. You no longer have to write your own registration or subscription retry logic.
• An out-of-the-box notification solution. You can use the Notifications composer, a serverless notifications solution with a web console that lets anyone send notifications to target specific audiences based on insights from Google Analytics.

To upgrade from GCM SDKs to FCM SDKs, see the guides for migrating Android and iOS apps.

Cloud Messaging: Why do my targeted devices apparently fail to receive messages?

When it looks like devices haven't successfully received messages, check first for these two potential causes:

Foreground message handling for notification messages. Client apps need to add message handling logic to handle notification messages when the app is in the foreground on the device. See the details for iOS and Android.

Network firewall restrictions. If your organization has a firewall that restricts the traffic to or from the Internet, you need to configure it to allow connectivity with FCM in order for your Firebase Cloud Messaging client apps to receive messages. The ports to open are:

• 5228
• 5229
• 5230

FCM usually uses 5228, but it sometimes uses 5229 and 5230. FCM does not provide specific IPs, so you should allow your firewall to accept outgoing connections to all IP addresses contained in the IP blocks listed in Google's ASN of 15169.

Cloud Messaging: I have implemented onMessageReceived in my Android app, but it is not being called.

When your app is in the background, notification messages are displayed in the system tray, and onMessageReceived is not called. For notification messages with a data payload, the notification message is displayed in the system tray, and the data that was included with the notification message can be retrieved from the intent launched when the user taps on the notification.

For more information, see Receive and handle messages.

Notifications composer: What's the difference between the Notifications composer and Cloud Messaging?

The Notifications composer is a lightweight, serverless messaging solution built on Firebase Cloud Messaging. With a user-friendly graphical console and reduced coding requirements, the Notifications composer lets users easily send messages to reengage and retain users, foster app growth, and support marketing campaigns.

Firebase Cloud Messaging provides a complete set of messaging capabilities through its client SDKs and HTTP and XMPP server protocols. For deployments with more complex messaging requirements, FCM is the right choice.

Here's a comparison of the messaging capabilities provided by Firebase Cloud Messaging and the Notifications composer:

Notifications composer: I am an existing Google Cloud Messaging (GCM) developer, and I want to use the Notifications composer. What should I do?

The Notifications composer is an out-of-the-box solution that lets anyone send notifications to target specific audiences based on insights from Google Analytics. Also, the Notifications composer provides funnel analysis for every message, allowing easy evaluation of notification effectiveness.

If you are an existing GCM developer, to use the Notifications composer you have to upgrade from GCM SDKs to FCM SDKs. See the guides for migrating Android and iOS apps.

Which FCM APIs were deprecated on June 20, 2023, and what should I do if I am using those APIs?

The following APIs/SDKs will be affected by the deprecation:

Server APIs

Firebase Admin SDK APIs

Client SDKs

Will I see a service downgrade before June 2024?

No. You have 12 months (06/20/2023 - 06/21/2024) to migrate from the old APIs to new APIs without any service downgrade. We strongly recommend you to plan the migration as early as possible so you won’t be impacted by the decommissioning of the APIs in June 2024.

After June 2024, you may see increased errors or lack of functionality when using the APIs/SDKs listed above.

What’s the difference between OAuth 2.0 tokens and server keys?

An OAuth 2.0 token is a short-lived token derived from a service account. It’s Google’s standard auth model and it’s more secure than static server keys.

See Use credentials to mint access tokens for guidance on using the Google Auth Library to obtain tokens.

Note that the request headers differ when you use OAuth 2.0 tokens for requests to different endpoints.

• HTTP v1 API: Authorization: Bearer $oauth_token
• Instance ID server API and Device group management API: Authorization: Bearer $oauth_token
access_token_auth: true

Can I migrate my requests to the new API all at once?

We recommend that you slowly ramp up your traffic to the new API. If you expect to send more than 600,000 messages/min on a regular basis, contact Firebase support for instructions on how to increase quota or get recommendations on how to spread out traffic.

What’s the difference between the HTTP v1 API and the legacy APIs when I send messages to topics/device groups?

Topics: you don’t need to add the "/topics/" prefix to your topic target when you use the v1 API.

Device groups: You can use a group token as a token target in the HTTP v1 API. However, the HTTP v1 API doesn’t return the success/failure counts in the response. We recommend that you use FCM topics or manage your device groups by yourself.

Does the HTTP v1 API support sending messages to multiple tokens in one request?

No. This feature, called "multicast" in legacy HTTP APIs, is not supported by the HTTP v1 API, which is better designed for scalability.

For use cases where end-to-end latency is critical, or where total fanout size is small (fewer than 1 million), Google recommends sending multiple separate requests using the HTTP v1 API. The HTTP v1 API over HTTP/2 performs similarly for 99.9% of multicast requests (sending

For use cases where throughput and egress bandwidth are prioritized or where total fanout size is large (greater than 1 million), Google recommends topic messaging. While topic messaging requires a one-time action to subscribe recipients to a topic, it offers up to a 10,000 QPS per project fanout rate without a maximum limit on topic size.

What versions of the Firebase Admin SDK have the new APIs?

What's the difference between the batch send API and the HTTP v1 API?

The FCM batch send API uses the same message format and authentication mechanism as the HTTP v1 API. However, it uses a different endpoint. If you want to improve efficiency, you should consider using HTTP/2 to send multiple requests over the same HTTP connection to the HTTP v1 API.

What should I do if I can't access my project?

Please reach out to the Google Cloud support team for help.

Can new projects enable the legacy Cloud Messaging API?

No. Starting from 5/20/2024, new projects will no longer be allowed to enable our legacy APIs.

Cloud Storage for Firebase: Why can't I use Cloud Storage for Firebase?

Cloud Storage for Firebase creates a default bucket in the App Engine no-cost tier. This allows you to quickly get up and running with Firebase and Cloud Storage for Firebase, without having to put in a credit card or enable a Cloud Billing account. It also allows you to easily share data between Firebase and a Google Cloud project.

There are, however, two known cases where this bucket cannot be created and you will be unable to use Cloud Storage for Firebase:

• A project imported from Google Cloud which had a App Engine Master/Slave Datastore application.
• A project imported from Google Cloud which has domain prefixed projects. For example: domain.com:project-1234.

There are currently no workarounds to these issues, and we recommend that you create a new project in the Firebase console and enable Cloud Storage for Firebase in that project.

Cloud Storage for Firebase: Why do I get error code 412 responses about service account permissions and failed service account operations when using the Cloud Storage for Firebase API?

It's likely you're getting 412 error codes either because the Cloud Storage for Firebase API is not enabled for your project or a necessary service account is missing the required permissions.

See the related FAQ.

Cloud Storage for Firebase: On Spark plan projects, can I store executable files?

For no-cost (Spark) plan projects, Firebase blocks uploads and hosting of certain executable file types for Windows, Android and Apple by Cloud Storage for Firebase and Firebase Hosting. This policy exists to prevent abuse on our platform.

Serving, hosting and file uploads of disallowed files are blocked for all Spark projects created on or after Sept 28th, 2023. For existing Spark projects with files uploaded before that date, such files can still be uploaded and hosted.

This restriction applies to Spark plan projects. Projects on the pay as you go (Blaze) plan are not affected.

The following file types cannot be hosted on Firebase Hosting and Cloud Storage for Firebase:

• Windows files with .exe, .dll and .bat extensions
• Android files with .apk extension
• Apple platform files with .ipa extension

What do I need to do?

If you still want to host these file types after September 28th, 2023:

• For Hosting: upgrade to the Blaze plan before you can deploy these file types to Firebase Hosting via the firebase deploy command.
• For Storage: upgrade to the Blaze plan to upload these file types to the bucket of your choice using the GCS CLI, the Firebase console, or Google Cloud console.

Use Firebase tools to manage your Firebase Hosting and Cloud Storage resources.

• For managing resources in Firebase Hosting, use the Firebase console to delete releases according to this guide.
• For managing resources in Cloud Storage, navigate to the Storage product page in your project.

1. On the Files tab, locate disallowed files to delete in your folder hierarchy, then select them using the checkbox next to the filename(s) on the left-hand side of the panel.
2. Click Delete, and confirm the files were deleted.

Please refer to our documentation for additional information on managing Hosting resources with Firebase tools and Cloud Storage for Firebase buckets with client libraries.

Cloud Storage for Firebase: Why do I see an unexpected increase in upload and download operations?

Previously, download and upload requests to the Cloud Storage for Firebase API were not being counted properly. We have taken steps to fix this issue, starting from September 15, 2023.

For Blaze users, upload and download operations will start counting towards your monthly bill. For Spark users, they will start counting towards your monthly free limit.

We recommend monitoring your Usage page for any increases that may count towards your limits.

Cloud Storage for Firebase: Why do I see new service account IDs associated with my Firebase projects that use Cloud Storage for Firebase?

Firebase uses service accounts to operate and manage services without sharing user credentials. When you create a Firebase project, you might notice that a number of service accounts are already available in your project.

The service account that Cloud Storage for Firebase uses is scoped to your project and is named
service-PROJECT_NUMBER@gcp-sa-firebasestorage.iam.gserviceaccount.com.

If you used Cloud Storage for Firebase before September 19, 2022, you may see an additional service account on previously-linked Cloud Storage buckets named firebase-storage@system.gserviceaccount.com. As of September 19, 2022, this service account is no longer supported.

You can view all service accounts associated with your project in the Firebase console, on the Service accounts tab.

Adding the new service account

If you removed the service account previously or the service account is not present in your project, you may do one of the following to add the account.

• (Recommended) Automated: Use the AddFirebase REST endpoint to re-import your bucket into Firebase. You will only need to call this endpoint once, not once for each linked bucket.
• Manual: Follow the steps in Creating and managing service accounts. Following that guide, add a service account with the IAM roleCloud Storage for Firebase Service Agent, and service account name
  service-PROJECT_NUMBER@gcp-sa-firebasestorage.iam.gserviceaccount.com.

Removing the new service account

We strongly discourage you from removing the service account because this may block access to your Cloud Storage buckets from your apps. To remove the service account from your project, follow the instructions in Disabling a service account.

Dynamic Links: What are Firebase's future plans for Dynamic Links?

See Dynamic Links FAQ.

Dynamic Links: Why does my Android app access each Dynamic Link twice?

The getInvitation API clears the saved Dynamic Link to prevent it from being accessed twice. Be sure to call this API with the autoLaunchDeepLink parameter set to false in each of the deep link activities to clear it for the case when the activity is triggered outside the main activity.

Why do Emulator Suite logs show an error starting with "Multiple projectIds are not recommended in single project mode"?

This message means the Emulator Suite has detected it may be running a particular product emulator using different project IDs. This may indicate a misconfiguration, and can cause issues when emulators try to communicate with one another, and when you try to interact with emulators from your code. If project IDs don't match, it often appears that data is missing, since data stored in emulators is keyed to projectID, and interoperability depends on matching project IDs.

This has been a common source of confusion among developers, so by default the Local Emulator Suite will now only allow running with a single project ID, unless you specify otherwise in the firebase.json configuration file. If an emulator detects more than one project ID, it will log a warning and potentially throw a fatal error.

Check your project ID declaration(s) for mismatches in:

• The default project set at the command line. By default, the project ID will be taken on startup from the project selected with firebase init or firebase use. To view the list of projects (and see which one is selected) use firebase projects:list.
• Unit tests. The project ID is often specified in calls to the Rules Unit Testing library methods initializeTestEnvironment or initializeTestApp. Other testing code may initialize with initializeApp(config).
• The command line --project flag. Passing the Firebase CLI --project flag overrides the default project. You'll need to ensure the value of the flag matches the project ID in unit tests and app initialization.

Platform-specific places to check:

To disable single project mode, update firebase.json with the singleProjectMode key:

{
  "firestore": {
    ...
  },
  "functions": {
    ...
  },
  "hosting": {
    ...
  },
  "emulators": {
    "singleProjectMode": false,
    "auth": {
      "port": 9099
    },
    "functions": {
      "port": 5001
    },
    ...
  }
}

Hosting: On Spark plan projects, can I store executable files?

For no-cost (Spark) plan projects, Firebase blocks uploads and hosting of certain executable file types for Windows, Android and Apple by Cloud Storage for Firebase and Firebase Hosting. This policy exists to prevent abuse on our platform.

Serving, hosting and file uploads of disallowed files are blocked for all Spark projects created on or after Sept 28th, 2023. For existing Spark projects with files uploaded before that date, such files can still be uploaded and hosted.

This restriction applies to Spark plan projects. Projects on the pay as you go (Blaze) plan are not affected.

The following file types cannot be hosted on Firebase Hosting and Cloud Storage for Firebase:

• Windows files with .exe, .dll and .bat extensions
• Android files with .apk extension
• Apple platform files with .ipa extension

What do I need to do?

If you still want to host these file types after September 28th, 2023:

• For Hosting: upgrade to the Blaze plan before you can deploy these file types to Firebase Hosting via the firebase deploy command.
• For Storage: upgrade to the Blaze plan to upload these file types to the bucket of your choice using the GCS CLI, the Firebase console, or Google Cloud console.

Use Firebase tools to manage your Firebase Hosting and Cloud Storage resources.

• For managing resources in Firebase Hosting, use the Firebase console to delete releases according to this guide.
• For managing resources in Cloud Storage, navigate to the Storage product page in your project.

1. On the Files tab, locate disallowed files to delete in your folder hierarchy, then select them using the checkbox next to the filename(s) on the left-hand side of the panel.
2. Click Delete, and confirm the files were deleted.

Please refer to our documentation for additional information on managing Hosting resources with Firebase tools and Cloud Storage for Firebase buckets with client libraries.

Hosting: Why does my Hosting release history table in the Firebase console show file counts that are more than what my local project actually has?

Firebase automatically adds extra files containing metadata about the Hosting site, and these files are included in the total file count for the release.

Hosting: What's the largest file size that I can deploy to Firebase Hosting?

Hosting has a maximum size limit of 2 GB for individual files.

We recommend storing larger files using Cloud Storage, which offers a maximum size limit in the terabyte range for individual objects.

Hosting: How many Hosting sites can I have per Firebase project?

The Firebase Hosting multisite feature supports a maximum of 36 sites per project.

Performance Monitoring: How many custom URL patterns can I create?

You can create up to 400 total custom URL patterns per app and up to 100 custom URL patterns per domain for that app.

Performance Monitoring: Why am I not seeing real time display of performance data?

To view real time performance data, make sure that your app uses a Performance Monitoring SDK version that's compatible with real time data processing.

• iOS — v7.3.0 or later
• tvOS — v8.9.0 or later
• Android — v19.0.10 or later (or Firebase Android BoM v26.1.0 or later)
• Web — v7.14.0 or later

Note that we always recommend using the latest version of SDK, but any version listed above will enable Performance Monitoring to process your data in near real time.

Realtime Database: Why was my Realtime Database reported bandwidth lower than average between September 2016 and March 2017?

For our bandwidth calculations, we normally include SSL encryption overhead (based on layer 5 of the OSI model). However, in September 2016, we introduced a bug that caused our bandwidth reporting to ignore encryption overhead. This might have resulted in artificially low reported bandwidth and bills on your account for a few months.

We released a fix for the bug in late March 2017, returning bandwidth reporting and billing to their normal levels.

Realtime Database: What are the scaling limitations of the Realtime Database?

Each Realtime Database instance has limits on the number of write operations per second. For small writes, this limit is approximately 1000 write operations per second. If you are approaching this limit, batching operations using multi-path updates can help you achieve higher throughput.

In addition, each database instance has a cap on the number of simultaneous database connections. Our default limits are large enough for most applications. If you are building an app that requires additional scale, you may need to shard your application across multiple database instances for added scale. You may also consider Cloud Firestore as an alternative database.

Realtime Database: What can I do if I'm over my Realtime Database usage limits?

If you've received an email alert or notification in the Firebase console that you've exceeded your Realtime Database usage limits, you can address it based on the usage limit you've exceeded. To see your Realtime Database usage, go to the Realtime Database Usage dashboard in the Firebase console.

If you're over your download limit, you can upgrade your Firebase pricing plan or wait until your download limit resets at the start of your next billing cycle. To decrease your downloads, try the following steps:

• Add queries to limit the data that your listen operations return.
• Check for unindexed queries.
• Use listeners that only download updates to data — for example, on() instead of once().
• Use security rules to block unauthorized downloads.

If you're over your storage limit, upgrade your pricing plan to avoid service disruptions. To reduce the amount of data in your database, try the following steps:

• Run periodic cleanup jobs.
• Reduce any duplicate data in your database.

Note that it may take some time to see any data deletions reflected in your storage allotment.

If you're over your simultaneous database connections limit, upgrade your plan to avoid any service disruptions. To manage simultaneous connections to your database, try connecting via users via the REST API if they don't require a realtime connection.

Remote Config: Why don't fetched values change the behavior and appearance of my app?

Unless you fetch values with fetchAndActivate(), values are stored locally but not activated. To activate fetched values so that they can take effect, call activate. This design lets you control when the behavior and appearance of your app changes, because you can choose when to call activate. After you call activate, your app source code determines when updated parameter values are used.

For example, you could fetch values and then activate them the next time a user starts your app, which removes the need to delay app startup while your app waits for fetched values from the service. Changes to your app's behavior and appearance then occur when your app uses the updated parameter values.

To learn more about the Remote Config API and usage model, see Remote Config API Overview.

Remote Config: I am making a lot of fetch requests while developing my app. Why doesn't my app always get the latest values from the service when it sends fetch requests?

During app development, you might want to fetch and activate configs very frequently (many times per hour) to let you rapidly iterate as you develop and test your app. To accommodate rapid iteration on a project with up to 10 developers, you can temporarily set a FirebaseRemoteConfigSettings object with a low minimum fetch interval (setMinimumFetchIntervalInSeconds) in your app.

Remote Config: How quickly does the Remote Config service return fetched values after my app sends a fetch request?

Devices usually receive fetched values in less than a second, and often receive fetched values in milliseconds. The Remote Config service handles fetch requests within milliseconds, but the time required to complete a fetch request will depend on the network speed of the device and the latency of the network connection used by the device.

If your goal is to make fetched values take effect in your app as soon as possible, but without creating a jarring user experience, consider adding calls to fetchAndActivate each time that your app does a full screen refresh.

What is Firebase User Segmentation Storage?

Firebase User Segmentation Storage stores Firebase installation IDs and related attributes and segments as well as audience lists you've created to provide targeting information to other Firebase services that use them, such as Crashlytics, FCM, Remote Config personalization, and more.