Get Started

Before you can take advantage of our SDK, you need to install the module(s) you want to use, initialize the SDK, and understand the order of operations.

This page is part of an introductory series to help you get started with the essential features of our SDK. The highlighted step(s) below are covered on this page. Before you continue, make sure you've implemented previous features—i.e. you can't identify people before you initialize the SDK!

graph LR getting-started(Install SDK) -->B(Initialize SDK) B --> identify(identify people) identify -.-> track-events(Send events) identify -.-> register-token(Register
Device Token) register-token -.-> push(Receive push) register-token -.-> rich-push(Receive Rich Push) track-events --> test-support(Write tests) push --> test-support rich-push --> test-support identify -.-> in-app(Receive in-app) in-app --> test-support click getting-started href "/docs/sdk/ios/getting-started/#install" click B href "/docs/sdk/ios/getting-started/#initialize-the-sdk" click identify href "/docs/sdk/ios/identify" click track-events href "/docs/sdk/ios/track-events/" click register-token href "/docs/sdk/ios/push" click push href "/docs/sdk/ios/push" click rich-push href "/docs/sdk/ios/rich-push" click in-app href "/docs/sdk/ios/in-app" click test-support href "/docs/sdk/ios/test-support" style getting-started fill:#B5FFEF,stroke:#007069 style B fill:#B5FFEF,stroke:#007069

How it works

Our SDKs provide a ready-made integration to identify people who use mobile devices and send them notifications. Before you start using the SDK, you should understand a bit about how the SDK works with

sequenceDiagram participant A as Mobile User participant B as SDK participant C as A--xB: User activity
user not identified A->>B: Logs in (identify method) rect rgb(229, 254, 249) Note over A,C: Now you can Send events and receive messages B-->>C: Person added/updated in CIO A->>B: User activity (track event) B->>C: Event triggers campaign C->>B: Campaign triggered push B->>A: Display push A->>B: Logs out (clearIdentify method) end A--xB: No longer sending events or receiving messages

You must identify a person before you can take advantage of most SDK features. We don’t currently support messages or events for anonymous devices/users, which means that we can’t track or respond to anything your audience does in your app until you identify them.

In, you identify people by id or email, which typically means that you need someone to log in to your app or service before you can identify them.

While someone is “identified”, you can send events representing their activity in your app to You can also send the identified person messages from

You send messages to a person through the campaign builder, broadcasts, etc. These messages are not stored on the device side. If you want to send an event-triggered campaign to a mobile device, the mobile device user must be identified and have a connection such that it can send an event back to and receive a message payload.

SDK package products

To minimize our SDK’s impact on your app’s size, we offer multiple, separate SDKs. You should only install the packages that you need for your project.

You must install the Tracking package. It lets you identify people, which you must do before you can send them messages, track their events, etc.

Package ProductRequired?Description
Trackingidentify people in
MessagingPushAPNReceive push notifications over Apple’s Push Notification Service (APNs)
MessagingPushFCMReceive push notifications over Google Firebase Cloud Messaging (FCM)
messagingInAppReceive in-app notifications


To support the SDK, you must:

  • Set iOS 13 or later as your minimum deployment target in XCode

  • Have an iOS 13+ device to test your implementation. You cannot test push notifications in a simulator.

Install the SDK

Follow Apple’s instructions to add as a dependency to your project in Xcode and select the individual package products that you want to install.

We recommend that you set the Dependency Rule to Up to Next Major Version. While we encourage you to keep your app up to date with the latest SDK, major versions can include breaking changes or new features that require your attention.

select up to next major version when installing the sdk
select up to next major version when installing the sdk

Install with CocoaPods

We typically recommend that you install the SDK using Swift Package Manager (SPM). However, if your app uses CocoaPods, you can find and install our pods by appending CustomerIO/ to our packages—e.g. CustomerIO/Tracking.

Package ProductRequired?Description
CustomerIO/Trackingidentify people in
CustomerIO/MessagingPushAPNReceive push notifications over Apple’s Push Notification Service (APNs)
CustomerIO/MessagingPushFCMReceive push notifications over Google Firebase Cloud Messaging (FCM)
CustomerIO/MessagingInAppReceive in-app notifications

Initialize the SDK

Before you can use the SDK, you need to initialize it. Any calls that you make to the SDK before you initialize it are ignored. The SDK uses a Singleton. You’ll need Track API credentials to initialize the SDK—your Site IDEquivalent to the user name you’ll use to interface with the Journeys Track API; also used with our JavaScript snippets. You can find your Site ID under Settings > Workspace Settings > API Credentials and API KeyEquivalent to the password you’ll use with a Site ID to interface with the Journeys Track API. You can generate new keys under Settings > Workspace Settings > API Credentials, which you can find in under Settings > Workspace Settings > API Credentials.

  1. To get started, initialize the SDK. You’ll usually do this in the AppDelegate application(_ application: didFinishLaunchingWithOptions) function.

     import CioTracking
     class AppDelegate: NSObject, UIApplicationDelegate {
         func application(
             _ application: UIApplication,
             didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]? = nil
         ) -> Bool {
             CustomerIO.initialize(siteId: "YOUR SITE ID", apiKey: "YOUR API KEY", region: Region.US) { config in }
             // The last parameter of `initialize()` is configuration. Ready for you to tweak if you wish. 
             CustomerIO.initialize(siteId: "YOUR SITE ID", apiKey: "YOUR API KEY", region: Region.US) { config in 
                 config.autoTrackScreenViews = true 
             return true
  2. When you want to use any of the SDK features, you use the shared instance of the class.


 Check out our sample apps!

Our repository provides real-world examples that you can help you see how the SDK works and implement it in your own apps.

Configuration options

You need to call configuration options when you initialize the SDK. The last parameter of initialize() contains your configuration options.

CustomerIO.initialize(siteId: "YOUR SITE ID", apiKey: "YOUR API KEY", region: Region.US) { config in 
    config.autoTrackScreenViews = true 

When you initialize the SDK, you can pass configuration options. In most cases, you'll want to stick with the defaults, but you might do things like change the logLevel when testing updates to your app or enable autoTrackScreenViews to automatically capture screen view events for your audience.

autoTrackDeviceAttributesbooleantrueAutomatically gathers information about devices, like operating system, device locale, model, app version, etc
autoTrackPushEventsbooleantrueThe SDK automatically generates delivered and opened metrics for push notifications sent from
autoTrackScreenViewsbooleanfalseIf true, the SDK automatically sends screen events for every screen your audience visits.
autoScreenViewBodystringsWhen autoTrackScreenViews is true, use this to override the the body of automatic screen view events. See automatic screen tracking for more information.
backgroundQueueMinNumberOfTasksinteger10See the processing queue for more information. This sets the number of tasks that enter the processing queue before sending requests to In general, we recommend that you don't change this setting, because it can impact your audience's battery life.
backgroundQueueSecondsDelayinteger30See the processing queue for more information. The number of seconds after a task is added to the processing queue before the queue executes. In general, we recommend that you don't change this setting, because it can impact your audience's battery life.
logLevelstringerrorSets the level of logs you can view from the SDK. Set to debug to see more logging output.

The Processing Queue

The SDK automatically adds all calls to a queue system, and waits to perform these calls until certain criteria is met. This queue makes things easier, both for you and your users: it handles errors and retries for you (even when users lose connectivity), and it can save users’ battery life by batching requests.

The queue holds requests until any one of the following criteria is met:

  • There are 10 or more tasks in the queue.
  • 30 seconds have passed since the SDK performed its last task.
  • The app is closed and re-opened.

For example, when you identify a new person in your app using the SDK, you won’t see the created/updated person immediately. You’ll have to wait for the SDK to meet any of the criteria above before the SDK sends a request to the API. Then, if the request is successful, you’ll see your created/updated person in your workspace.

How the queue organizes tasks

The SDK typically runs tasks in the order that they were called—unless one of the tasks in the queue fails.

Tasks in the queue are grouped by “type” because some tasks need to run sequentially. For example, you can’t invoke a track call if an identify call hasn’t succeeded first. So, if a task fails, the SDK chooses the next task in the queue depending on whether or not the failed task is the first task in a group.

  • If the failed task is the first in a group: the SDK skips the remaining tasks in the group, and moves to the next task outside the group.
  • If the failed task is 1+n task in a group: the SDK skips the failed task and moves on to the next task in the group.**

The following chart shows how the SDK would process a queue where tasks A, B, and C belong to the same group.

flowchart TD a["Task inventory
[A, B, C], D"]-->b{Is task A
successful} b-.->|Yes|c[Continue to task B] b-.->|No|d[Skip to task D] c-.->|Whether task B
succeeds or fails|E[Continue to task C]

Using the SDK as a Data Pipelines source

The SDK uses our Journeys Track API, but our SDK can also double as a source of data in our Data Pipelines feature without any additional development work.

If you want to forward data from your mobile app to other applications in your stack using our Data Pipelines feature, you can enable the Track API as a source. This automatically forwards calls from your app to Data Pipelines without having to implement new calls or functions. We’ll translate calls from the SDK to the Data Pipelines format, so you can take advantage of your mobile data in destinations automatically.

When you enable the Track API as a data source, you’ll see individual sources for each set of Track API credentials. The Name of your credentials becomes the name of your data source.

all API credentials are listed as individual sources
all API credentials are listed as individual sources
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