iOS SDK (Beta)

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

Getting started¶

Use this quickstart guide to get started with Amplitude iOS SDK.

Usage¶

Initialize¶

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

let amplitude = Amplitude(configuration: Configuration(
    apiKey: 'YOUR-API-KEY'
))

Configuration¶

track¶

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)

Another way to instrument basic tracking event.

amplitude.track(
    eventType: "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. Starting from release v0.4.0, identify events with only set operations will be batched and sent with fewer events. This change won't affect running the set operations. There is a config identifyBatchIntervalMillis for managing the interval to flush the batched identify intercepts.

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)

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 multiple group names
amplitude.setGroup(groupType: "sport", groupName: ["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]
    )
)

Group identify¶

Use the Group Identify API to set or update 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: groupIdentify)

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)

Custom user ID¶

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

amplitude.setUserId(userId: "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)

Reset when 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 SDK plugin¶

Plugins allow you to extend Amplitude SDK's behavior by, for example, modifying event properties (enrichment type) or sending to a 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. The expected return value is null. 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.

Plugin examples¶

Enrichment type plugin¶

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())

Destination type plugin¶

In destination plugin, you are able to overwrite the track(), identify(), groupIdentify(), revenue(), 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
    }
}

Advanced topics¶

User sessions¶

A session on iOS is a period of time that a user has the app in the foreground.

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 30 minutes.

let amplitude = Amplitude(
    configuration: Configuration(
        apiKey: "YOUR-API-KEY",
        minTimeBetweenSessionsMillis: 1000
    )
)

By default, Amplitude automatically sends the '[Amplitude] Start Session' and '[Amplitude] End Session' events. Even though these events aren't sent, sessions are still tracked by using session_id. You can also disable those session events.

let amplitude = Amplitude(
    configuration: Configuration(
        apiKey: "YOUR-API-KEY",
        trackingSessionEvents: false
    )
)

You can define your own session expiration time. The default session expiration time is 30 minutes.

let amplitude = Amplitude(
    configuration: Configuration(
        apiKey: "YOUR-API-KEY",
        minTimeBetweenSessionsMillis: 100000
    )
)

Set custom user ID¶

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

amplitude.setUserId(userId: "USER_ID")

Don't assign users a user ID that could change, because each unique user ID is a unique user in Amplitude. Learn more about how Amplitude tracks unique users in the Help Center.

Log level¶

You can 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.

amplitude.logger?.logLevel = LogLevelEnum.LOG.rawValue

Logged out and anonymous users¶

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();

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.disableCity().disableIpAddress().disableLatLng()
let amplitude = Amplitude(
    configuration: Configuration(
        apiKey: "YOUR-API-KEY",
        trackingOptions: trackingOptions
    )
)

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: "YOUR-API-KEY",
        enableCoppaControl: true
    )
)

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.

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: "YOUR-API-KEY",
        optOut: true
    )
)

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: "YOUR-API-KEY",
        loggerProvider: SampleLogger()
    )
)

More resources¶

If you have any problems or issues with the SDK, create a GitHub issue or submit a request on Amplitude Help.