# Optimizely Feature Experimentation Device Mode Integration

RudderStack lets you send the experimentation data from your mobile apps to Optimizely Feature Experimentation via [device mode]({{< ref "destinations/rudderstack-connection-modes.md#device-mode" >}}).

## Prerequisites

Unlike other destinations, Optimizely Feature Experimentation for the mobile integration works a little differently. You will have to implement some Optimizely functions natively to make sure the experiment logic runs correctly.

{{< info >}}
RudderStack maps the `track` calls with Optimizely's `track` calls. You need to implement all Optimizely's decision-based methods like `activate` and `isFeatureEnabled` natively. For more details, refer to Optimizely's [Easy Event Tracking](https://blog.optimizely.com/2019/02/26/introducing-easy-event-tracking-the-easier-way-to-understand-and-optimize-the-customer-journey/) blog and the [Optimizely SDK reference Guide](https://docs.developers.optimizely.com/full-stack/docs/sdk-reference-guides#section-ios-and-tvos).
{{< /info >}}

## Adding Optimizely to your mobile project

{{< tabs tabTotal="2" >}}
{{% tab tabName="Android (Java) — Legacy" %}}
Follow these steps to add Optimizely Feature Experimentation to your Android Project:
1. Add the following `repository` to your `app/build.gradle` file.

```groovy
repositories {
    mavenCentral()
}
```

2. After that, add the following `dependency` in the same file:

```groovy
implementation 'com.rudderstack.android.integration:optimizely:0.1.1'
implementation 'com.optimizely.ab:android-sdk:3.0.0'
```

3. Initialize the Optimizely Manager:

{{< warning >}}
Optimizely recommends initializing their SDK as soon as possible. You need to initialize the Optimizely Manager before proceeding to the next step. Refer to the Optimizely [Initializing the SDK](https://docs.developers.optimizely.com/full-stack/docs/initialize-sdk-android) guide for more information.
{{< /warning >}}


```groovy
val optimizelyManager =  OptimizelyManager.builder()
            .withSDKKey(<YOUR OPTIMIZELY SDK KEY>)
            .build(this)
```

4. Finally, change the initialization of your `RudderClient` in your `Application` class:

```groovy
val rudderClient = RudderClient.getInstance(
    this,
    <YOUT_WRITE_KEY>,
    RudderConfig.Builder()
        .withEndPointUri(<YOUR_DATA_PLANE_URL>)
        .withFactory(OptimizelyIntegrationFactory.FACTORY(optimizelyManager)
        .build()
)
```

{{< warning >}}
Make sure you pass the Optimizely manager instance you created in the previous step to the factory as shown in the above snippet above.
{{< /warning >}}

{{% /tab %}}
{{% tab tabName="iOS (Obj-C) — Legacy" %}}
Follow these steps to add Optimizely Feature Experimentation to your iOS project:

1. Go your `Podfile` and add the `Rudder-Optimizely` extension:

```objectivec
pod 'Rudder-Optimizely'
```

2. After adding the dependency followed by `pod install`, you can add the imports to your `AppDelegate.m` file as shown:

```objectivec
#import "RudderOptimizelyFactory.h"
```

3. Finally, change the initialization of your `RudderClient` as shown:

```objectivec
RSConfigBuilder *builder = [[RSConfigBuilder alloc] init];
[builder withDataPlaneUrl:DATA_PLANE_URL];
// Setup optimizely logger.
OPTLYLoggerDefault *optlyLogger = [[OPTLYLoggerDefault alloc] initWithLogLevel:OptimizelyLogLevelAll];
// Create an Optimizely manager
 self.optlyManager = [[OPTLYManager alloc] initWithBuilder:[OPTLYManagerBuilder  builderWithBlock:^(OPTLYManagerBuilder * _Nullable builder) {
        builder.sdkKey = @<SDK KEY>;
        builder.logger = optlyLogger;
 }]];
[builder withFactory:[RudderOptimizelyFactory instanceWithOptimizely:self.optlyManager]];
[builder withLoglevel:RSLogLevelDebug];
[RSClient getInstance:WRITE_KEY config:[builder build]];
```

{{% /tab %}}
{{< /tabs >}}