> For the complete documentation index, see [llms.txt](https://docs.hackle.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.hackle.io/en/development-guide/quick-start.md).

# Quick Start

This guide shows you how to integrate the Hackle SDK to run A/B Tests and collect events.

{% hint style="info" %}
You can find your SDK Key in the Hackle Dashboard under **Settings > SDK Integration Info**.
{% endhint %}

{% tabs %}
{% tab title="Android" %}
{% stepper %}
{% step %}
**Install SDK**

Add the dependency to `build.gradle`.

```gradle
repositories {
    mavenCentral()
}

dependencies {
    implementation 'io.hackle:hackle-android-sdk:2+'
}
```

{% endstep %}

{% step %}
**Initialize SDK**

```kotlin
import io.hackle.android.Hackle
import io.hackle.android.initialize

Hackle.initialize(applicationContext, "YOUR_APP_SDK_KEY") {
    // SDK initialization complete
}
```

{% endstep %}

{% step %}
**Variation Distribution**

Pass the Experiment Key to determine the user's variation.

```kotlin
val hackleApp = Hackle.app()
val variation = hackleApp.variation(EXPERIMENT_KEY)

if (variation == Variation.A) {
    // Group A
} else if (variation == Variation.B) {
    // Group B
}
```

{% endstep %}

{% step %}
**Event Tracking**

Track user behavior events.

```kotlin
hackleApp.track("EVENT_KEY")
```

{% endstep %}
{% endstepper %}

For detailed options at each step, refer to the [Android SDK documentation](/en/development-guide/android.md).
{% endtab %}

{% tab title="iOS" %}
{% stepper %}
{% step %}
**Install SDK**

Install via Swift Package Manager or CocoaPods.

**Swift Package Manager**

```
https://github.com/hackle-io/hackle-ios-sdk.git
```

**CocoaPods**

```ruby
pod 'Hackle'
```

{% endstep %}

{% step %}
**Initialize SDK**

```swift
import Hackle

Hackle.initialize(sdkKey: "YOUR_APP_SDK_KEY") {
    // SDK initialization complete
}
```

{% endstep %}

{% step %}
**Variation Distribution**

Pass the Experiment Key to determine the user's variation.

```swift
let hackleApp = Hackle.app()
let variation = hackleApp.variation(experimentKey: EXPERIMENT_KEY)

if variation == "A" {
    // Group A
} else if variation == "B" {
    // Group B
}
```

{% endstep %}

{% step %}
**Event Tracking**

Track user behavior events.

```swift
hackleApp.track(eventKey: "EVENT_KEY")
```

{% endstep %}
{% endstepper %}

For detailed options at each step, refer to the [iOS SDK documentation](/en/development-guide/ios.md).
{% endtab %}

{% tab title="JavaScript" %}
{% stepper %}
{% step %}
**Install SDK**

Install via npm.

```bash
npm install @hackler/javascript-sdk
```

{% endstep %}

{% step %}
**Initialize SDK**

```javascript
import * as Hackle from "@hackler/javascript-sdk";

const hackleClient = Hackle.createInstance("YOUR_BROWSER_SDK_KEY");
```

{% endstep %}

{% step %}
**Variation Distribution**

Pass the Experiment Key to determine the user's variation.

```javascript
hackleClient.onReady(function () {
    const variation = hackleClient.variation(EXPERIMENT_KEY);

    if (variation === "A") {
        // Group A
    } else if (variation === "B") {
        // Group B
    }
});
```

{% endstep %}

{% step %}
**Event Tracking**

Track user behavior events.

```javascript
hackleClient.track({ key: "EVENT_KEY" });
```

{% endstep %}
{% endstepper %}

For detailed options at each step, refer to the [JavaScript SDK documentation](/en/development-guide/javascript.md).
{% endtab %}
{% endtabs %}


---

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