Analytics Kotlin Amplitude Plugin

Amplitude is an event tracking and segmentation platform for your web and mobile apps. By analyzing the actions your users perform, you can gain a better understanding to drive retention, engagement, and conversion.

Getting started

1. Before you start, go to your Amplitude workspace. Click Settings in the bottom left, then click Projects in the left menu. Select your Project. Copy the Amplitude API Key and Secret Key for the project.
2. From the Segment web app, click Catalog, then click Destinations.
3. Find the Destinations Actions item in the left navigation, and click it.
4. Click the “Amplitude” item to select it and click Configure.
5. Choose which of your sources to connect the destination to. (You can connect more sources to the destination later.)

Once you have a mapping, you can follow the steps in the Destinations Actions documentation on Customizing mappings.

The Amplitude Kotlin plugin doesn’t send events to Amplitude from the client side. It instead adds Amplitude session data and then sends it server side from the Amplitude Actions destination.

Adding the dependency

To install the Segment-Amplitude integration, simply add this line to your gradle file:

implementation 'com.segment.analytics.kotlin.destinations:amplitude:<latest_version>'

Or the following for Kotlin DSL

implementation('com.segment.analytics.kotlin.destinations:amplitude:<latest_version>')

Using the Plugin in your App

Open the file where you setup and configure the Analytics-Kotlin library. Add this plugin to the list of imports.

import com.segment.analytics.kotlin.destinations.amplitude.AmplitudeSession

Just under your Analytics-Kotlin library setup, call analytics.add(plugin = …) to add an instance of the plugin to the Analytics timeline.

    analytics = Analytics("<YOUR WRITE KEY>", applicationContext) {
        this.flushAt = 3
        this.trackApplicationLifecycleEvents = true
    }
    analytics.add(plugin = AmplitudeSession())

Your events will now begin to flow to Amplitude in device mode.

Log Purchases in existing destination instances

Initially, the Log Event Action was reporting purchases to Amplitude for all events containing a products array, even if the products were just added to cart. This inflated the LTV Chart in Amplitude.

To resolve this, purchase reporting takes place in a new Action called Log Purchase.

For instances created prior to before the Log Purchases action was released, you need to manually add the Log Purchases Action to report purchases to Amplitude.

To manually add the Log Purchases Action:

1. Add a new Mapping for the Log Purchases Action. The default trigger for this action is Order Completed events.
2. Modify the Trigger if you need to report purchases for any other events.
3. Modify the Trigger of Log Event to exclude these same events. This helps you to avoid sending the same event twice.
4. Enable the Log Purchases mapping.

Connection Modes for Amplitude (Actions) destination

The Amplitude (actions) destination does not offer a device-mode connection mode. If you’re using one of Segment’s new libraries (Analytics.js 2.0, Swift or Kotlin) with the Actions-framework version of the destination, you do not need the device-mode connection.

Most previous deployments of the Amplitude Segment destination used the device-mode connection to use the session_id tracking feature. The new Actions-framework Amplitude destination, includes session ID tracking by default. This means you don’t need to bundle any software to run on the user’s device, or write any code. It also means that you can use more of the Segment platform features on data going to Amplitude, such as Protocols filtering and transformations, and Profiles Identity Resolution.

Session tracking is available with Segment’s new libraries: Analytics.js 2.0, Swift or Kotlin

Device ID Mappings

The Amplitude destination requires that each event include either a Device ID or a User ID. If a User ID isn’t present, Amplitude uses the a Device ID, and vice versa, if a Device ID isn’t present, Amplitude uses the User ID.

By default, Segment maps the Segment property context.device.id to the Amplitude property Device ID. If context.device.id isn’t available, Segment maps the property anonymousId to the Amplitude Device ID. The Actions interface indicates this with the following contents of the Device ID field: coalesce( context.device.id anonymousId ).

Enable Amplitude session tracking

To enable session tracking in Amplitude when using the Segment Kotlin library:

1. Enable trackApplicationLifecycleEvents in your configuration.
2. Add the Amplitude Session plugin to your project.
3. Initialize the plugin

   analytics.add(AmplitudeSession())
   

Important differences from the classic Amplitude destination

The classic Amplitude destination captures the following user fields in device-mode (when it runs on the user’s device):

• Device Type (for example, Mac, PC, mobile device)
• Platform (for example iOS or Android)

Amplitude (Actions) runs in cloud-mode, and does not capture these fields.

Available Actions

Build your own Mappings. Combine supported triggers with the following -supported actions:

Amplitude (Actions) uses Amplitude’s HTTP API v2

You configure the Amplitude (Actions) destination through Filters and Actions. Consult the table below for information about configuring your Amplitude (Actions) destination similarly to your classic Amplitude destination.

Amplitude settings mapping

Advanced Amplitude (Actions) settings

Increment Traits

The traitsToIncrement setting increases a user property by some numerical value. If the user property does not have a value set yet, Segment initializes it with a value of 0. The trait must have a numerical value so it can be incremented.

In the following example, the Amplitude User property friendCount equals 4.

"traits" : {"$add": {"friendCount": 3} }
"traits" : {"$add": {"friendCount": 1} }