iOS Swift SDK

This is the official documentation for the Amplitude Analytics iOS SDK.

Install the SDK

github "amplitude/Amplitude-Swift" ~> 1.0

Initialize the SDK

You must initialize the SDK before you can instrument. The API key for your Amplitude project is required.

let amplitude = Amplitude(configuration: Configuration(
    apiKey: AMPLITUDE_API_KEY,
    autocapture: .all
))

AMPConfiguration *configuration = [AMPConfiguration initWithApiKey:AMPLITUDE_API_KEY];
configuration.autocapture = AMPAutocaptureOptions.all;
Amplitude *amplitude = [Amplitude initWithConfiguration:configuration];

Configure the SDK

Track events

Events represent how users interact with your application. For example, "Button Clicked" may be an action you want to note.

let event = BaseEvent(
    eventType: "Button Clicked", 
    eventProperties: ["my event prop key": "my event prop value"]
)
amplitude.track(event: event)

AMPBaseEvent *event = [AMPBaseEvent initWithEventType:@"Button Clicked"
    eventProperties:@{@"my event prop key": @"my event prop value"}];

[amplitude track:event];

Another way to instrument basic tracking event.

amplitude.track(
    eventType: "Button Clicked",
    eventProperties: ["my event prop key": "my event prop value"]
)

[amplitude track:@"Button Clicked" eventProperties:@{
    @"my event prop key": @"my event prop value"
}];

Identify

Identify is for setting the user properties of a particular user without sending any event. The SDK supports the operations set, setOnce, unset, add, append, prepend, preInsert, postInsert, and remove on individual user properties. Declare the operations via a provided Identify interface. You can chain together multiple operations in a single Identify object. The Identify object is then passed to the Amplitude client to send to the server.

You can handle the identity of a user using the identify methods. Proper use of these methods can connect events to the correct user as they move across devices, browsers, and other platforms. Send an identify call containing those user property operations to Amplitude server to tie a user's events with specific user properties.

let identify = Identify()
identify.set(property: "color", value: "green")
amplitude.identify(identify: identify)

AMPIdentify *identify = [AMPIdentify new];
[identify set:@"color" value:@"green"];
[amplitude identify:identify];

Autocapture

Starting from release v1.8.0, the SDK is able to track more events without manual instrumentation. It can be configured to track the following events automatically:

• Sessions
• App lifecycles
• Screen views
• Element interactions
• Frustration interactions
  • Rage clicks
  • Dead clicks
• Network requests

You can configure Amplitude to start tracking Autocapture events. Otherwise, you can omit the configuration to keep only session tracking enabled.

let amplitude = Amplitude(configuration: Configuration(
    apiKey: "API_KEY",
    autocapture: [.sessions, .appLifecycles, .screenViews, .networkTracking]
))

let amplitude = Amplitude(configuration: Configuration(
    apiKey: "API_KEY",
    autocapture: .appLifecycles 	// or use `[]` to disable Autocapture.
))

AMPConfiguration *configuration = [AMPConfiguration initWithApiKey:@"API_KEY"];
configuration.autocapture = [[AMPAutocaptureOptions alloc] initWithOptionsToUnion:@[
    AMPAutocaptureOptions.sessions,
    AMPAutocaptureOptions.appLifecycles,
    AMPAutocaptureOptions.screenViews,
    AMPAutocaptureOptions.networkTracking
]];
Amplitude *amplitude = [Amplitude initWithConfiguration:configuration];

AMPConfiguration *configuration = [AMPConfiguration initWithApiKey:@"API_KEY"];
configuration.autocapture = [[AMPAutocaptureOptions alloc] initWithOptionsToUnion:@[AMPAutocaptureOptions.appLifecycles]];   // or use an empty array to disable Autocapture.
Amplitude *amplitude = [Amplitude initWithConfiguration:configuration];

Remote configuration for autocapture

Starting from release v1.10.0, the SDK supports remote configuration for autocapture settings. This feature allows you to update autocapture settings after initialization without requiring an app update.

By default, remote configuration for autocapture is enabled. You can disable it by setting enableAutoCaptureRemoteConfig to false in the configuration:

let amplitude = Amplitude(configuration: Configuration(
    apiKey: "API_KEY",
    autocapture: [.sessions, .appLifecycles, .screenViews],
    enableAutoCaptureRemoteConfig: false
))

AMPConfiguration *configuration = [AMPConfiguration initWithApiKey:@"API_KEY"];
configuration.autocapture = [[AMPAutocaptureOptions alloc] initWithOptionsToUnion:@[
    AMPAutocaptureOptions.sessions,
    AMPAutocaptureOptions.appLifecycles,
    AMPAutocaptureOptions.screenViews
]];
configuration.enableAutoCaptureRemoteConfig = NO;
Amplitude *amplitude = [Amplitude initWithConfiguration:configuration];

When you enable remote configuration, the SDK checks for updates to Autocapture settings in your project. If updates are available, the SDK applies them automatically. This allows you to:

• Enable or disable specific autocapture features remotely
• Change autocapture settings without requiring users to update the app

Changes made through remote configuration affect future events and don't apply to events that are already tracked.

Track sessions

Amplitude enables session tracking by default. Include AutocaptureOptions.sessions in the autocapture configuration to explicitly configure the SDK to track session events or to enable session event tracking along with other Autocapture configurations.

let amplitude = Amplitude(configuration: Configuration(
    apiKey: "API_KEY",
    autocapture: .sessions
))

AMPConfiguration *configuration = [AMPConfiguration initWithApiKey:@"API_KEY"];
configuration.autocapture = [[AMPAutocaptureOptions alloc] initWithOptionsToUnion:@[AMPAutocaptureOptions.sessions]];
Amplitude *amplitude = [Amplitude initWithConfiguration:configuration];

For more information about session tracking, see User sessions.

Track application lifecycles

You can enable Amplitude to start tracking application lifecycle events by including AutocaptureOptions.appLifecycles in the autocapture configuration.

let amplitude = Amplitude(configuration: Configuration(
    apiKey: "API_KEY",
    autocapture: .appLifecycles
))

AMPConfiguration *configuration = [AMPConfiguration initWithApiKey:@"API_KEY"];
configuration.autocapture = [[AMPAutocaptureOptions alloc] initWithOptionsToUnion:@[AMPAutocaptureOptions.appLifecycles]];
Amplitude *amplitude = [Amplitude initWithConfiguration:configuration];

When you enable this setting, Amplitude tracks the following events:

• [Amplitude] Application Installed, this event fires when a user opens the application for the first time right after installation, by observing the UIApplicationDidFinishLaunchingNotification notification underneath.
• [Amplitude] Application Updated, this event fires when a user opens the application after updating the application, by observing the UIApplicationDidFinishLaunchingNotification notification underneath.
• [Amplitude] Application Opened, this event fires when a user launches or foregrounds the application after the first open, by observing the UIApplicationDidFinishLaunchingNotification or UIApplicationWillEnterForegroundNotification notification underneath.
• [Amplitude] Application Backgrounded, this event fires when a user backgrounds the application, by observing the UIApplicationDidEnterBackgroundNotification notification underneath.

Track screen views

You can enable Amplitude to start tracking screen view events by including AutocaptureOptions.screenViews in the autocapture configuration.

// UIKit
let amplitude = Amplitude(configuration: Configuration(
    apiKey: "API_KEY",
    autocapture: .screenViews
))

// Swift UI
let amplitude = Amplitude(configuration: Configuration(
    apiKey: "API_KEY",
    autocapture: []
))
amplitude.track(ScreenViewedEvent(screenName: "Screen Name"))

// UIKit
AMPConfiguration *configuration = [AMPConfiguration initWithApiKey:@"API_KEY"];
configuration.autocapture = [[AMPAutocaptureOptions alloc] initWithOptionsToUnion:@[AMPAutocaptureOptions.screenViews]];
Amplitude *amplitude = [Amplitude initWithConfiguration:screenViews];

// Swift UI
configuration.autocapture = [[AMPAutocaptureOptions alloc] initWithOptionsToUnion:@[]];
[amplitude track:[AMPScreenViewedEvent initWithScreenName:@"Screen Name"]];

When you enable this setting, Amplitude tracks the [Amplitude] Screen Viewed event and sets the screen name property of this event to the name of the top-most view controller's class. Amplitude reads this value from the controller class metadata viewDidAppear method swizzling.

Track network requests

You can enable Amplitude to start tracking network requests by including AutocaptureOptions.networkTracking in the autocapture configuration.

let amplitude = Amplitude(configuration: Configuration(
    apiKey: "API_KEY",
    autocapture: .networkTracking
))

AMPConfiguration *configuration = [AMPConfiguration initWithApiKey:@"API_KEY"];
configuration.autocapture = [[AMPAutocaptureOptions alloc] initWithOptionsToUnion:@[AMPAutocaptureOptions.networkTracking]];
Amplitude *amplitude = [Amplitude initWithConfiguration:configuration];

With the default configuration, the SDK tracks network requests from all hosts (except *.amplitude.com) with status code 500 to 599. To customize the tracking behavior, set Configuration.networkTrackingOptions with NetworkTrackingOptions.

captureRules: [
    .init(hosts: ["*"], statusCodeRange: "400-499,500-599"),
    .init(hosts: ["*.example.com", "example.com"], statusCodeRange: "0,500-599"),
]

The default configuration tracks all hosts except *.amplitude.com with status code 500 to 599.

Example use:

// Style 1: Use the default configuration and append a new rule
let networkTrackingOptions = NetworkTrackingOptions.default // contain a rule for all hosts, statusCodeRange: "500-599"
networkTrackingOptions.captureRules.append(
    .init(hosts: ["*.example.com", "example.com"], statusCodeRange: "0,500-599")
)
networkTrackingOptions.ignoreHosts.append("notmyapi.com")

let amplitude = Amplitude(configuration: Configuration(
    apiKey: "API_KEY",
    autocapture: .networkTracking,
    networkTrackingOptions: networkTrackingOptions,
))

// Style 2: Create a new configuration with a custom rule
let amplitude = Amplitude(configuration: Configuration(
    apiKey: "API_KEY",
    autocapture: .networkTracking,
    networkTrackingOptions: .init(
        captureRules: [
            .init(hosts: ["*"]), // all hosts, statusCodeRange: "500-599"
            .init(hosts: ["*.example.com", "example.com"], statusCodeRange: "0,400-599"),
        ],
        ignoreHosts: ["notmyapi.com"]
    ),
))

// Style 1: Use the default configuration and append a new rule
AMPNetworkTrackingOptions *networkTrackingOptions = AMPNetworkTrackingOptions.defaultOptions;  // contain a rule for all hosts, statusCodeRange: "500-599"
NSMutableArray<AMPNetworkTrackingCaptureRule *> *rules = [networkTrackingOptions.captureRules mutableCopy];
[rules addObject:[[AMPNetworkTrackingCaptureRule alloc] initWithHosts:@[@"*.example.com", @"example.com"] statusCodeRange:@"0,400-599"]];
networkTrackingOptions.captureRules = rules;

// Style 2: Create a new configuration with a custom rule
NSArray<AMPNetworkTrackingCaptureRule *> *rules = @[
    [[AMPNetworkTrackingCaptureRule alloc] initWithHosts: @[@"*"] statusCodeRange:@"500-599"],
    [[AMPNetworkTrackingCaptureRule alloc] initWithHosts: @[@"*.example.com", @"example.com"] statusCodeRange:@"0,400-599"]
];
AMPNetworkTrackingOptions *networkTrackingOptions = [[AMPNetworkTrackingOptions alloc] initWithCaptureRules:rules
                                                                                                ignoreHosts:@[@"notmyapi.com"]
                                                                                    ignoreAmplitudeRequests:true];

// Then use the configuration to initialize the Amplitude instance
AMPConfiguration *configuration = [AMPConfiguration initWithApiKey:@"API_KEY"];
configuration.autocapture = [[AMPAutocaptureOptions alloc] initWithOptionsToUnion:@[AMPAutocaptureOptions.networkTracking]];
configuration.networkTrackingOptions = networkTrackingOptions;
Amplitude *amplitude = [Amplitude initWithConfiguration:configuration];

When you enable this setting, Amplitude tracks the [Amplitude] Network Request event whenever the application makes a network request. The SDK swizzles URL loading system methods to instrument network activity.

@_spi(NetworkTracking) import Amplitude-Swift

let amplitude = Amplitude(configuration: Configuration(
    apiKey: "API_KEY",
    autocapture: .networkTracking,
    networkTrackingOptions: .init(
        captureRules: [
            .init(hosts: ["*"]), // all hosts, statusCodeRange: "500-599"
            .init(urls: [.regex("^https://example\\.com/api/.*"), .exact("https://example.com/api2/status")],
                  methods: ["POST"],
                  statusCodeRange: "0,400-599",
                  requestHeaders: .init(allowlist: ["Link", "X-API-Key"]),
                  responseHeaders: .init(allowlist: ["Link", "X-API-Key"], captureSafeHeaders: false),
                  requestBody: .init(allowlist: ["user/*", "product/**/id"]),
                  responseBody: .init(allowlist: ["profile/**"], blocklist: ["**/password"])),
        ],
        ignoreHosts: ["notmyapi.com"],
        ignoreAmplitudeRequests: true
    ),
))

Track deep links

Deeplink tracking isn't automated. To track deeplinks, track the corresponding events.

let amplitude = Amplitude(configuration: Configuration(
    apiKey: "API_KEY"
))

amplitude.track(DeepLinkOpenedEvent(url: URL()))
amplitude.track(DeepLinkOpenedEvent(url: "url", referrer:"referrer"))
amplitude.track(DeepLinkOpenedEvent(activity: activity))

AMPConfiguration *configuration = [AMPConfiguration initWithApiKey:@"API_KEY"];
Amplitude *amplitude = [Amplitude initWithConfiguration:configuration];

[amplitude track:[AMPDeepLinkOpenedEvent initWithUrl:@"url"]];
[amplitude track:[AMPDeepLinkOpenedEvent initWithUrl:@"url" referrer:@"referrer"]];
[amplitude track:[AMPDeepLinkOpenedEvent initWithActivity:activity]];

Amplitude tracks the [Amplitude] Deep Link Opened event with the URL and referrer information.

Track element interactions

Amplitude can track user interactions with UIControl elements and UIGestureRecognizer objects in UIKit applications. To enable this option, include AutocaptureOptions.elementInteractions in the autocapture configuration.

let amplitude = Amplitude(configuration: Configuration(
    apiKey: "API_KEY",
    autocapture: .elementInteractions
))

AMPConfiguration *configuration = [AMPConfiguration initWithApiKey:@"API_KEY"];
configuration.autocapture = [[AMPAutocaptureOptions alloc] initWithOptionsToUnion:@[AMPAutocaptureOptions.elementInteractions]];
Amplitude *amplitude = [Amplitude initWithConfiguration:configuration];

After enabling this setting, Amplitude tracks the [Amplitude] Element Interacted event whenever a user interacts with an element in the application. The SDK swizzles the UIApplication.sendAction(_:to:from:for:) method and the UIGestureRecognizer.state property setter to instrument UIControl action methods and UIGestureRecognizer within the application, respectively.

Track frustration interactions

Available in version 1.15.0+.

Amplitude can track frustration interactions (Rage Clicks and Dead Clicks) with UIControl elements and UIGestureRecognizer objects in UIKit applications. To enable this option, include AutocaptureOptions.frustrationInteractions in the autocapture configuration.

let amplitude = Amplitude(configuration: Configuration(
    apiKey: "API_KEY",
    autocapture: .frustrationInteractions
))

The interactionsOptions configuration accepts an InteractionsOptions object to configure the options for capturing rage clicks and dead clicks.

let amplitude = Amplitude(configuration: Configuration(
    apiKey: "API_KEY",
    autocapture: .frustrationInteractions,
    interactionsOptions: .init(
        rageClick: .init(enabled: true),
        deadClick: .init(enabled: true)
    )
))

Rage Click is a user interaction that occurs four (4) or more times in 1 second on the same element and the distance between each adjacent click is no more than 50 points.

When a Rage Click occurs, Amplitude tracks the [Amplitude] Rage Click event.

Dead Click is a tap on an interactive element that resulted in no visible change in the following three (3) seconds.

When a Dead Click occurs, Amplitude tracks the [Amplitude] Dead Click event.

User groups

Amplitude supports assigning users to groups and performing queries, such as Count by Distinct, on those groups. If at least one member of the group has performed the specific event, then the count includes the group.

For example, you want to group your users based on what organization they're in by using an 'orgId'. Joe is in 'orgId' '10', and Sue is in 'orgId' '15'. Sue and Joe both perform a certain event. You can query their organizations in the Event Segmentation Chart.

When setting groups, define a groupType and groupName. In the previous example, 'orgId' is the groupType and '10' and '15' are the values for groupName. Another example of a groupType could be 'sport' with groupName values like 'tennis' and 'baseball'.

Setting a group also sets the groupType:groupName as a user property, and overwrites any existing groupName value set for that user's groupType, and the corresponding user property value. groupType is a string, and groupName can be either a string or an array of strings to indicate that a user is in multiple groups.

// set group with a single group name
amplitude.setGroup(groupType: "orgId", groupName: "15")

// set group with a single group name
[amplitude setGroup:@"orgId" groupName:@"15"];

// set group with multiple group names
amplitude.setGroup(groupType: "sport", groupName: ["tennis", "soccer"])

// set group with multiple group names
[amplitude setGroup:@"sport" groupNames:@[@"tennis", @"soccer"]];

You can also set event-level groups by passing an Event Object with groups to track. With event-level groups, the group designation applies only to the specific event being logged, and doesn't persist on the user unless you explicitly set it with setGroup.

amplitude.track(
    event: BaseEvent(
        eventType: "event type",
        eventProperties: [
            "eventPropertyKey": "eventPropertyValue"
        ], 
        groups: ["orgId": "15"]
    )
)

AMPBaseEvent *event = [AMPBaseEvent initWithEventType:@"event type"
    eventProperties:@{@"eventPropertyKey": @"eventPropertyValue"}];
[event.groups set:@"orgId" value:@"15"];
[amplitude track:event];

Group identify

Use the Group Identify API to set or update the properties of particular groups. Keep these considerations in mind:

• Updates affect only future events, and don't update historical events.
• You can track up to 5 unique group types and 10 total groups.

The groupIdentify method accepts a group type string parameter and group name object parameter, and an Identify object that's applied to the group.

let groupType = "plan"
let groupName = "enterprise"
let identify = Identify().set(property: "key", value: "value")
amplitude.groupIdentify(groupType: groupType, groupName: groupProperty, identify: identify)

NSString *groupType = @"plan";
NSString *groupName = @"enterprise";
AMPIdentify *identify = [AMPIdentify new];
[identify set:@"key" value:@"value"];
[amplitude groupIdentify:groupType groupName:groupName identify:identify];

Track revenue

Amplitude can track revenue generated by a user. Revenue is tracked through distinct revenue objects, which have special fields that are used in Amplitude's Event Segmentation and Revenue LTV charts. This allows Amplitude to automatically display data relevant to revenue in the platform. Revenue objects support the following special properties, as well as user-defined properties through the eventProperties field.

let revenue = Revenue()
revenue.price = 3.99
revenue.quantity = 3
revenue.productId = "com.company.productId"
amplitude.revenue(revenue: revenue)

AMPRevenue *revenue = [AMPRevenue new];
revenue.price = 3.99;
revenue.quantity = 3;
revenue.productId = @"com.company.productId";
[amplitude revenue:revenue];

Custom user ID

If your app has its login system that you want to track users with, you can call setUserId at any time.

amplitude.setUserId(userId: "user@amplitude.com")

[amplitude setUserId:@"user@amplitude.com"];

Custom device ID

You can assign a new device ID using deviceId. When setting a custom device ID, make sure the value is sufficiently unique. Amplitude recommends using a UUID.

amplitude.setDeviceId(NSUUID().uuidString)

[amplitude setDeviceId:[[NSUUID UUID] UUIDString]];

Custom storage

If you don't want to store the data in the Amplitude-defined location, you can customize your own storage by implementing the Storage protocol and setting the storageProvider in your configuration.

Every iOS app gets a slice of storage just for itself, meaning that you can read and write your app's files there without worrying about colliding with other apps. By default, Amplitude uses this file storage and creates an "amplitude" prefixed folder inside the app "Documents" directory. However, if you need to expose the Documents folder in the native iOS "Files" app and don't want expose "amplitude" prefixed folder, you can customize your own storage provider to persist events on initialization.

Amplitude(
    configuration: Configuration(
        apiKey: AMPLITUDE_API_KEY,
        storageProvider: YourOwnStorage() // YourOwnStorage() should implement Storage
    )
)

Reset when the user logs out

reset is a shortcut to anonymize users after they log out, by:

• setting userId to null
• setting deviceId to a new value based on current configuration

With an empty userId and a completely new deviceId, the current user would appear as a brand new user in dashboard.

amplitude.reset()

[amplitude reset];

Plugins

Plugins enable you to extend Amplitude SDK's behavior by, for example, modifying event properties (enrichment type) or sending to third-party APIs (destination type). A plugin is an object with methods setup() and execute().

Plugin.setup

This method contains logic for preparing the plugin for use and has amplitude instance as a parameter. A typical use for this method, is to instantiate plugin dependencies. This method is called when the plugin is registered to the client via amplitude.add().

Plugin.execute

This method contains the logic for processing events and has event instance as parameter. If used as enrichment type plugin, the expected return value is the modified/enriched event. If used as a destination type plugin, the expected return value is null. This method is called for each event, including Identify, GroupIdentify and Revenue events, that's instrumented using the client interface.

Enrichment type plugin example

Here's an example of a plugin that modifies each event that's instrumented by adding extra event property.

class EnrichmentPlugin: Plugin {
    let type: PluginType
    var amplitude: Amplitude?

    init() {
        self.type = PluginType.enrichment
    }

    func setup(amplitude: Amplitude) {
        self.amplitude = amplitude
    }

    func execute(event: BaseEvent?) -> BaseEvent? {
        event?.sessionId = -1
        if event?.eventProperties == nil {
            event?.eventProperties = [:]
        }
        event?.eventProperties?["event prop key"] = "event prop value"
        return event
    }
}

amplitude.add(plugin: EnrichmentPlugin())

[amplitude add:[AMPPlugin initWithType:AMPPluginTypeEnrichment
    execute:^AMPBaseEvent *_Nullable(AMPBaseEvent * _Nonnull event) {
    event.sessionId = -1;
    [event.eventProperties set:@"event prop key" value:@"event prop value"];
    return event;
}]];

Destination type plugin example

In destination plugins, you can overwrite the track(), identify(), groupIdentify(), revenue(), and flush() functions.

class TestDestinationPlugin: DestinationPlugin {
    override func track(event: BaseEvent) -> BaseEvent? {
        return event
    }

    override func identify(event: IdentifyEvent) -> IdentifyEvent? {
        return event
    }

    override func groupIdentify(event: GroupIdentifyEvent) -> GroupIdentifyEvent? {
        return event
    }

    override func revenue(event: RevenueEvent) -> RevenueEvent? {
        return event
    }

    override func flush() {
    }

    override func setup(amplitude: Amplitude) {
        self.amplitude = amplitude
    }

    override func execute(event: BaseEvent?) -> BaseEvent? {
        return event
    }
}

[amplitude add:[AMPPlugin initWithType:AMPPluginTypeDestination
    execute:^AMPBaseEvent * _Nullable(AMPBaseEvent * _Nonnull event) {
    if ([event.eventType isEqualToString:@"$identify"]) {
        // ...
    } else if ([event.eventType isEqualToString:@"$groupidentify"]) {
        // ...
    } else if ([event.eventType isEqualToString:@"revenue_amount"]) {
        // ...
    } else {
        // ...
    }
    return nil;
} flush:^() {
    // ...
}]];

Troubleshooting and debugging

Ensure that the configuration and payload are accurate and check for any unusual messages during the debugging process. If everything appears to be right, check the value of flushQueueSize or flushIntervalMillis. Events are queued and sent in batches by default, which means they are not immediately dispatched to the server. Ensure that you have waited for the events to be sent to the server before checking for them in the charts.

Log

• Set the log level to debug to collect useful information during debugging.
• Customize loggerProvider class from the LoggerProvider and implement your own logic, such as logging error message in server in a production environment.

Plugin

Take advantage of a Destination Plugin to print out the configuration value and event payload before sending them to the server. You can set the logLevel to debug, copy the following TroubleShootingPlugin into your project, add the plugin into the Amplitude instance.

SwiftUI TroubleShootingPlugin example.

Event callback

The event callback executes after the event is sent, for both successful and failed events. Use this method to monitor the event status and message. For more information, see configuration > callback.

Advanced topics

User sessions

Amplitude starts a session when the app is brought into the foreground or when an event is tracked in the background. A session ends when the app remains in the background for more than the time set by setMinTimeBetweenSessionsMillis() without any event being tracked. Note that a session will continue for the entire time the app is in the foreground no matter whether session tracking is enabled by configuration.defaultTracking, configuration.autocapture or not.

When the app enters the foreground, Amplitude tracks a session start, and starts a countdown based on setMinTimeBetweenSessionsMillis(). Amplitude extends the session and restarts the countdown any time it tracks a new event. If the countdown expires, Amplitude waits until the next event to track a session end event.

Amplitude doesn't set user properties on session events by default. To add these properties, use identify() and setUserId(). Amplitude aggregates the user property state and associates the user with events based on device_id or user_id.

Due to the way in which Amplitude manages sessions, there are scenarios where the SDK works expected but it may appear as if events are missing or session tracking is inaccurate:

• If a user doesn't return to the app, Amplitude doesn't track a session end event to correspond with a session start event.
• If you track an event in the background, it's possible that Amplitude perceives the session length to be longer than the user spends on the app in the foreground.
• If you modify user properties between the last event and the session end event, the session end event reflects the updated user properties, which may differ from other properties associated with events in the same session. To address this, use an enrichment plugin to set event['$skip_user_properties_sync'] to true on the session end event, which prevents Amplitude from synchronizing properties for that specific event. See $skip_user_properties_sync in the Converter Configuration Reference article to learn more.

Amplitude groups events together by session. Events that are logged within the same session have the same session_id. Sessions are handled automatically so you don't have to manually call startSession() or endSession().

You can adjust the time window for which sessions are extended. The default session expiration time is five minutes.

Use the helper method getSessionId to get the value of the current sessionId.

let amplitude = Amplitude(
    configuration: Configuration(
        apiKey: AMPLITUDE_API_KEY,
        minTimeBetweenSessionsMillis: 1000
    )
)

AMPConfiguration *configuration = [AMPConfiguration initWithApiKey:AMPLITUDE_API_KEY];
configuration.minTimeBetweenSessionsMillis = 1000;
Amplitude *amplitude = [Amplitude initWithConfiguration:configuration];

You can also track events as out-of-session. Out-of-session events have a sessionId of -1 and behave as follows:

1. Aren't part of the current session.
2. Don't extend the current session.
3. Don't start a new session.
4. Don't change the sessionId for subsequent events.

A potential use case is for events tracked from push notifications, which are usually external to the customers app usage.

Set the sessionId to -1 in EventOptions to mark an event as out-of-session when you call track(event, options) or identify(identify, options).

let outOfSessionOptions = EventOptions(sessionId: -1)

amplitude.identify(
    event: Identify().set(property: "user-prop", value: true),
    options: outOfSessionOptions
)

amplitude.track(
    event: BaseEvent(eventType: "Button Clicked"),
    options: outOfSessionOptions
)

AMPEventOptions *outOfSessionOptions = [AMPEventOptions new];
outOfSessionOptions.sessionId = -1;

AMPIdentify *identify = [AMPIdentify new];
[identify set:@"user-prop" value:YES];
[amplitude identify:identify options:outOfSessionOptions];

AMPBaseEvent *event = [AMPBaseEvent initWithEventType:@"Button Clicked"];
[amplitude track:event options:outOfSessionOptions];

Log level

control the level of logs that print to the developer console.

• 'OFF': Suppresses all log messages.
• 'ERROR': Shows error messages only.
• 'WARN': Shows error messages and warnings. This level logs issues that might be a problem and cause some oddities in the data. For example, this level would display a warning for properties with null values.
• 'LOG': Shows informative messages about events.
• 'DEBUG': Shows error messages, warnings, and informative messages that may be useful for debugging.

Set the log level logLevel with the level you want.

let amplitude = Amplitude(
    configuration: Configuration(
        apiKey: AMPLITUDE_API_KEY,
        logLevel: LogLevelEnum.LOG
    )
)

AMPConfiguration *configuration = [AMPConfiguration initWithApiKey:AMPLITUDE_API_KEY];
configuration.logLevel = AMPLogLevelLOG;
Amplitude *amplitude = [Amplitude initWithConfiguration:configuration];

Amplitude merges user data, so any events associated with a known userId or deviceId are linked the existing user.
If a user logs out, Amplitude can merge that user's logged-out events to the user's record. You can change this behavior and log those events to an anonymous user instead.

To log events to an anonymous user:

1. Set the userId to null.
2. Generate a new deviceId.

Events coming from the current user or device appear as a new user in Amplitude. Note: If you do this, you can't see that the two users were using the same device.

amplitude.reset()

[amplitude reset];

Disable tracking

By default the iOS SDK tracks several user properties such as carrier, city, country, ip_address, language, and platform.
Use the provided TrackingOptions interface to customize and toggle individual fields.
Before initializing the SDK with your apiKey, create a TrackingOptions instance with your configuration and set it on the SDK instance.

let trackingOptions = TrackingOptions()
trackingOptions.disableTrackCity().disableTrackIpAddress()
let amplitude = Amplitude(
    configuration: Configuration(
        apiKey: AMPLITUDE_API_KEY,
        trackingOptions: trackingOptions
    )
)

AMPConfiguration *configuration = [AMPConfiguration initWithApiKey:AMPLITUDE_API_KEY];
[configuration.trackingOptions disableTrackCity];
[configuration.trackingOptions disableTrackIpAddress];
Amplitude *amplitude = [Amplitude initWithConfiguration:configuration];

Tracking for each field can be individually controlled, and has a corresponding method (for example, disableCountry, disableLanguage).

Carrier

Amplitude determines the user's mobile carrier using CTTelephonyNetworkInfo, which returns the registered operator of the sim.

COPPA control

COPPA (Children's Online Privacy Protection Act) restrictions on IDFA, IDFV, city, IP address and location tracking can all be enabled or disabled at one time. Apps that ask for information from children under 13 years of age must comply with COPPA.

let amplitude = Amplitude(
    configuration: Configuration(
        apiKey: AMPLITUDE_API_KEY,
        enableCoppaControl: true
    )
)

AMPConfiguration *configuration = [AMPConfiguration initWithApiKey:AMPLITUDE_API_KEY];
configuration.enableCoppaControl = true;
Amplitude *amplitude = [Amplitude initWithConfiguration:configuration];

Advertiser ID

Advertiser ID (also referred to as IDFA) is a unique identifier provided by the iOS and Google Play stores. As it's unique to every person and not just their devices, it's useful for mobile attribution.

Mobile attribution is the attribution of an installation of a mobile app to its original source (such as ad campaign, app store search). Mobile apps need permission to ask for IDFA, and apps targeted to children can't track at all. Consider using IDFV, device ID, or an email login system when IDFA isn't available.

To retrieve the IDFA and add it to the tracking events, you can follow this example plugin to implement your own plugin.

Device ID lifecycle

The SDK initializes the device ID in the following order, with the device ID being set to the first valid value encountered:

1. Device ID of Amplitude instance if it’s set by setDeviceId()
2. IDFV if it exists
3. A randomly generated UUID string

One user with multiple devices

A single user may have multiple devices, each having a different device ID. To ensure coherence, set the user ID consistently across all these devices. Even though the device IDs differ, Amplitude can still merge them into a single Amplitude ID, thus identifying them as a unique user.

Transfer to a new device

It's possible for multiple devices to have the same device ID when a user switches to a new device. When transitioning to a new device, users often transfer their applications along with other relevant data. The specific transferred content may vary depending on the application. In general, it includes databases and file directories associated with the app. However, the exact items included depend on the app's design and the choices made by the developers. If databases or file directories have been backed up from one device to another, the device ID stored within them may still be present. Consequently, if the SDK attempts to retrieve it during initialization, different devices might end up using the same device ID.

Get device ID

Use the helper method getDeviceId() to get the value of the current deviceId.

let deviceId = amplitude.getDeviceId()

NSString *deviceId = [amplitude getDeviceId];

To set the device, see custom device ID.

Location tracking

Amplitude converts the IP of a user event into a location (GeoIP lookup) by default. This information may be overridden by an app's own tracking solution or user data.

Opt users out of tracking

Users may wish to opt out of tracking entirely, which means Amplitude doesn't track any of their events or browsing history. OptOut provides a way to fulfill a user's requests for privacy.

let amplitude = Amplitude(
    configuration: Configuration(
        apiKey: AMPLITUDE_API_KEY,
        optOut: true
    )
)

AMPConfiguration *configuration = [AMPConfiguration initWithApiKey:AMPLITUDE_API_KEY];
configuration.optOut = true;
Amplitude *amplitude = [Amplitude initWithConfiguration:configuration];

Set log callback

Implements a customized loggerProvider class from the LoggerProvider, and pass it in the configuration during the initialization to help with collecting any error messages from the SDK in a production environment.

class SampleLogger: Logger {
    typealias LogLevel = LogLevelEnum

    var logLevel: Int

    init(logLevel: Int = LogLevelEnum.OFF.rawValue) {
        self.logLevel = logLevel
    }

    func error(message: String) {
        // TODO: handle error message
    }

    func warn(message: String) {
        // TODO: handle warn message
    }

    func log(message: String) {
        // TODO: handle log message
    }

    func debug(message: String) {
        // TODO: handle debug message
    }
}

let amplitude = Amplitude(
    configuration: Configuration(
        apiKey: AMPLITUDE_API_KEY,
        loggerProvider: SampleLogger()
    )
)

AMPConfiguration *configuration = [AMPConfiguration initWithApiKey:AMPLITUDE_API_KEY];
configuration.loggerProvider = ^(NSInteger logLevel, NSString * _Nonnull message) {
    switch(logLevel) {
    case AMPLogLevelERROR:
        // TODO: handle error message
        break;
    case AMPLogLevelWARN:
        // TODO: handle warn message
        break;
    case AMPLogLevelLOG:
        // TODO: handle log message
        break;
    case AMPLogLevelDEBUG:
        // TODO: handle debug message
        break;
    }
};
Amplitude *amplitude = [Amplitude initWithConfiguration:configuration];

Security

iOS automatically protects application data by storing each apps data in its own secure directory. This directory is usually not accessible by other applications. However, if a device is jailbroken, apps are granted root access to all directories on the device.

To prevent other apps from accessing your apps Amplitude data on a jailbroken device, Amplitude recommends setting a unique instance name for your SDK. This creates a unique database isolates it from other apps.

let amplitude = Amplitude(
    configuration: Configuration(
        apiKey: "API-KEY",
        instanceName: "my-unqiue-instance-name"
    )
)

AMPConfiguration *configuration = [AMPConfiguration initWithApiKey:@"API-KEY"
                                                    instanceName:@"my-unqiue-instance-name"];
Amplitude *amplitude = [Amplitude instanceWithConfiguration:configuration];

Offline mode

Beginning with version 1.3.0, the Amplitude iOS Swift SDK supports offline mode. The SDK checks network connectivity every time it tracks an event. If the device is connected to network, the SDK schedules a flush. If not, it saves the event to storage. The SDK also listens for changes in network connectivity and flushes all stored events when the device reconnects.

To disable offline mode, add offline: NetworkConnectivityCheckerPlugin.Disabled on initialization as shown below.

let amplitude = Amplitude(
    configuration: Configuration(
        apiKey: "API-KEY",
        offline: NetworkConnectivityCheckerPlugin.Disabled
    )
)

AMPConfiguration *configuration = [AMPConfiguration initWithApiKey:AMPLITUDE_API_KEY];
configuration.offline = AMPNetworkConnectivityCheckerPlugin.Disabled;
Amplitude *amplitude = [Amplitude initWithConfiguration:configuration];

You can also implement you own offline logic:

1. Disable the default offline logic as above.
2. Toggle amplitude.configuration.offline by yourself.

Apple privacy manifest

Starting December 8, 2020, Apple requires a privacy manifest file for all new apps and app updates. Apple expects to make this mandatory in the Spring of 2024. As Amplitude is a third-party to your app, you need to ensure you properly disclose to your users the ways you use Amplitude in regards to their data.

NSPrivacyTracking

By default, Amplitude doesn't use data for tracking. Add this field and set it to true if your app does.

NSPrivacyCollectedDataTypes

By default the SDK tracks deviceId only. You can use setUserId() to track userId as well. To do so, add the "User ID" Data type. For more information about data types, see Apple's article Describing data use in privacy manifests.

NSPrivacyTrackingDomains

If you set NSPrivacyTracking to true then you need to provide at least one internet domain in NSPrivacyTrackingDomains based on your configuraiton.

NSPrivacyAccessedAPITypes

The SDK only uses userDefaults API for identity storage.

Create your app's privacy report

Follow the steps on how to create your app's privacy.