Tracking Methods
iOS (Swift)

iOS (Swift)

Getting Started

Please refer to our Quickstart Guide.

The Full API Reference (opens in a new tab), Library Source Code (opens in a new tab), and an Example Application (opens in a new tab) is documented in our GitHub repo.

Sending Events

We recommend tracking only five to seven events in your application instead of tracking too many things to start. Ideally, you track users going through your initial user experience and one key metric that matters for your application (e.g. YouTube might choose "Watched Video" as a key metric).

Once you've initialized the library, you can track an event by calling track(event:properties:) (opens in a new tab) with the event name and properties.

Mixpanel.mainInstance().track(event: "Plan Selected",
    properties:["Plan": "Premium"])

Timing Events

You can track the time it took for an action to occur, such as an image upload or a comment post, using time(event:) (opens in a new tab). This will mark the "start" of your action, which you can then finish with a track call. The time duration is then recorded in the "Duration" property.

Mixpanel.mainInstance().time(event: "Image Upload")
//...some time later
Mixpanel.mainInstance().track(event: "Image Upload")

Super Properties

It's very common to have certain properties that you want to include with each event you send. Generally, these are things you know about the user rather than about a specific event—for example, the user's age, gender, or source.

To make things easier, you can register these properties as super properties. If you do, we will automatically include them with all tracked events. Super properties are saved to device storage, and will persist across invocations of your app. Mixpanel already stores some information as super properties by default; see a full list of Mixpanel default properties here.

To set super properties, call registerSuperProperties(_:) (opens in a new tab)

// Send a "Plan: Mega" property will be sent
// with all future track calls.
Mixpanel.mainInstance().registerSuperProperties(["Plan": "Mega"])

Going forward, whenever you track an event, super properties will be included as properties. For instance, if you call:

Mixpanel.mainInstance().track(event: "Signup",
    properties:["Source": "Twitter"])

after making the above call to registerSuperProperties, it is just like adding the properties directly:

Mixpanel.mainInstance().track(event: "Signup",
    properties:[ "Plan" : "Mega", "Source": "Twitter"])

Setting Super Properties Only Once

If you want to store a super property only once (often for things like ad campaign or source), you can use registerSuperPropertiesOnce(_:defaultValue:) (opens in a new tab). This function behaves like registerSuperProperties(_:) (opens in a new tab) and has the same interface, but it doesn't override super properties you've already saved.

Mixpanel.mainInstance().registerSuperPropertiesOnce(["Source": "ad-01"])

This means that it's safe to call registerSuperPropertiesOnce(_:defaultValue:) (opens in a new tab) with the same property on every app load, and it will only set it if the super property doesn't exist.

Super Properties Live in Local Storage

Our mobile libraries store your super properties in local storage. They will persist so long as the app is installed (between launches and updates). Uninstalling the app will remove that customers super properties.

Managing User Identity

You can handle the identity of a user using the identify and alias methods. Proper use of these methods can connect events to the correct user as they move across devices, browsers, and other platforms.


Identify a user with a unique ID to track user activity across devices, tie a user to their events, and create a user profile. If you never call this method, unique visitors are tracked using a UUID that generates the first time they visit the site.

Call identify when you know the identity of the current user, typically after log-in or sign-up. We recommend against using identify for anonymous visitors to your site.

// This example would set the identify the user with the new ID 13793
Mixpanel.mainInstance().identify(distinctId: "13793");

Call Reset on Logout

Reset generates a new random distinct_id and clears super properties. Call reset to clear data attributed to a user when that user logs out. This allows you to handle multiple users on a single device. For more information about maintaining user identity, see the Identifying Users article.

Beginning with version v2.7.7, Mixpanel no longer uses the IFA(ID for Advertisers) but uses a randomly generated UUID as the default distinct ID instead. After you call reset, Mixpanel generates a new distinct_id.

If you want to use IFV(identifierForVendor) as the distinct_id, you can set MIXPANEL_UNIQUE_DISTINCT_ID in build settings Active Compilation Conditions on the Mixpanel framework target. After you call reset, the IFV will not change. However, when a user removes and then re-installs the app, the IFV will change with each installation.

Storing User Profiles

In addition to events, you can store user profiles in Mixpanel's Behavioral Analytics product. Profiles are persistent sets of properties that describe a user - things like name, email address, and signup date. You can use profiles to explore and segment users by who they are, rather than what they did.

We generally recommend creating user profiles for only authenticated users; with this in mind, to create user profiles, 2 requiremenst need to be met:

  • You must call .identify() at least once for each user. Normally this is done after they authenticate.
  • At least one property should be sent for a profile to be created.

Note: when sending set or set_once operations, the library will also populate automatic properties like $ios_app_version, $ios_device_model, geo-location properties and others.

Setting Profile Properties

You can set properties on a user profile with people.set(property:to:) (opens in a new tab).

// Identify the authenticated user with the ID 13793
// You can skip this if it was already called during authentication
Mixpanel.mainInstance().identify(distinctId: "13793");
// Sets user 13793's "Plan" attribute to "Premium"
Mixpanel.mainInstance().people.set(properties: [ "plan":"Premium", "$email":""])

This will set a "Plan" property, with a value "Premium", on user 13793's profile. If there isn't a profile with distinct_id 13793 in Mixpanel already, a new profile will be created. If user 13793 already has a property named "Plan" in their profile, the old value will be overwritten with "Premium".

Incrementing Numeric Properties

You can use people.increment(property:by:) (opens in a new tab) to change the current value of numeric properties. This is useful when you want to keep a running tally of things, such as games played, messages sent, or points earned.

// Here we increment the user's point count by 500.
Mixpanel.mainInstance().people.increment(property: "point count",
    by: 500)
// Pass an NSDictionary to increment multiple properties
    ["dollars spent": 17, "credits remaining": -34])

Other Types of Profile Updates

There are a few other types of profile updates. To learn more, please review the full MixpanelPeople API documentation (opens in a new tab).

Tracking Revenue

Mixpanel makes it easy to analyze the revenue you earn from individual customers. By associating charges with user profiles, you can compare revenue across different customer segments and calculate things like lifetime value.

You can track a single transaction with people.trackCharge(amount:) (opens in a new tab). This call will add transactions to the individual user profile, which will also be reflected in the Mixpanel Revenue report.

// Tracks $100.77 in revenue for user 13793
Mixpanel.mainInstance().people.trackCharge(amount: 100.77)
// Refund this user 50 dollars
Mixpanel.mainInstance().people.trackCharge(amount: -50)

Group Analytics

Mixpanel Group Analytics is a paid add-on that allows behavioral data analysis by selected groups, as opposed to individual users.

Grouping by identifiers other than the distinct_id will allow analysis at a company or group level when using Mixpanel analytics. Read this article to learn more about Group Analytics.

A group is identified by the group_key and group_id.

  • group_key is the property that connects event data for Group Analytics.
  • group_id is the identifier for a specific group.

If the property “company” is chosen for Group Analytics, “company” is the group_key, and “Mixpanel”, “Company A”, and “13254” are all potential group_id values.

A user can belong to multiple groups. All updates to a group operate on the group_key and group_id.

Creating a Group Key

Administer group keys through your Project Settings. Group keys are event properties. All events need to have a defined group key on them in order to be attributed to a group. Group keys are project specific, and the group key should be set up before group data is sent. Note that Mixpanel does not backfill historical data before the group key was implemented.

To administer group keys, navigate to your Project Settings. Click +Add Group Key under the GROUP KEYS section.

Adding Users to a Group

Adding users to groups causes the group_key and group_id to send as a property key and value for all events triggered by that user on the device. You can add multiple values for a single user to the group_key list property.

Similar to a distinct_id, the group_key allows Mixpanel to group events by an identifier for analysis. A group_key, however, is a group level identifier and not a user level identifier like the distinct_id.

You can add users to groups by calling the setGroup() (opens in a new tab) method.

Mixpanel.mainInstance().setGroup(groupKey: "Company", groupID: “Mixpanel”)

You can call addGroup() (opens in a new tab) to add any additional groups to an existing list.

Mixpanel.mainInstance().addGroup(groupKey: "Company", groupID: “Mixpanel”)

You can call removeGroup() (opens in a new tab) to remove any additional groups from an existing list.

Mixpanel.mainInstance().removeGroup(groupKey: "Company", groupID: “Mixpanel”)

Creating Group Profiles

It is possible to create a Group profile that is similar to a user profile. You must call getGroup().set() (opens in a new tab) to build a group profile. It is important to the group_key, group_id, and one property so that the profile is not empty.

Mixpanel.mainInstance().getGroup(groupKey: "Company", groupID: “Mixpanel”).set(property: "g", to: "yo")

Setting Group Profile Properties

You can add details to Groups by adding properties to them.

In order to update Group profile properties, you must specify the group that needs to be updated by calling getGroup().set() (opens in a new tab).

Mixpanel.mainInstance().getGroup(groupKey: "Company", groupID: “Mixpanel”)

The getGroup() (opens in a new tab) method can be chained with other commands that edit properties specific to the group.

You can set the property $name to populate the name field at the top of the group profile.

These operations are similar to the corresponding operations for user profile property updates.


mixpanel.getGroup().set() (opens in a new tab) updates or adds a property to a group.

Mixpanel.mainInstance().getGroup(groupKey: "Company", groupID: “Mixpanel”).set(property: "g", to: "yo")

For all Group functions, see the reference (opens in a new tab)

Debugging and Logging

You can turn on Mixpanel logging by enabling the following flag:

Mixpanel.mainInstance().loggingEnabled = true

EU Data Residency

Route data to Mixpanel's EU servers by setting the serverURL property after initializing the client.

let mixpanel = Mixpanel.initialize(token: "MIXPANEL_TOKEN")
mixpanel.serverURL = ""

[Legacy] Automatically Tracked Events

Mixpanel's SDKs have a legacy feature to automatically collect common mobile events. We don't recommend enabling this, as these events rely on client-side state and can be unreliable.

Raw NameDisplay NameDescription
$ae_first_openFirst App OpenTracks the first time the user has opened the app. This event is retriggered if the user reinstalls the app or clears local storage. A user property First App Open Date ($ae_first_app_open_date) is tracked to indicate the date when app was first opened.
$ae_updatedApp UpdatedExecutes when a user updates the app from the previous version. A Version Updated ($ae_updated_version) property is tracked to store the new app version.
$ae_sessionApp SessionExecutes when a user spends more than 10 seconds in the app. A Session Length ($ae_session_length) property is tracked to reflect the number of seconds user spent in the session. In addition, there are two user properties tracked: Total App Sessions ($ae_total_app_sessions) and Total App Session Length ($ae_total_app_session_length).
$ae_iapIn App Purchase (IAP)Executes when a user conducts an in-app purchase through your app. Mixpanel provides three properties for this event: Product Name ($ae_iap_name), Product Quantity ($ae_iap_quantity), and Product Price ($ae_iap_price).

Release History

See All Releases (opens in a new tab).

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