# Initialize the SDK in iOS

> Initialize the Unity Ads SDK in your iOS app. Set your Game ID and use a delegate to manage initialization callbacks and enable ad monetization.

> **Important:**
>
> Initialize the SDK early in your project's run-time life cycle before you need to show ads.

## ViewController.h

In your `ViewController` header (`.h`), import Unity Ads and set the following delegates:

* `UnityAdsInitializationDelegate` handles callbacks for initialization succeeding or failing.
* `UnityAdsLoadDelegate` handles callbacks for Ad Units succeeding or failing to load content.
* `UnityAdsShowDelegate` handles callbacks for Ad Units succeeding or failing to show loaded content.

1. **Objective-C**

   ```objective-c
   #import <UnityAds/UnityAds.h>

   @interface ViewController : UIViewController<UnityAdsInitializationDelegate,
   UnityAdsLoadDelegate,
   UnityAdsShowDelegate>

   @property (assign, nonatomic) BOOL testMode;
   ```

## ViewController.m

To initialize the SDK, you must reference your project's Game ID for the appropriate platform. You can locate the ID in the [Unity Ads Monetization dashboard](https://cloud.unity.com/monetization) by selecting **CURRENT PROJECT** > **Settings** from the secondary navigation menu

In your `ViewController` implementation (`.m`), create a `UnityAdsInitializationDelegate` delegate to handle initialization callbacks, and reference it as a parameter in the `initialize` method.

## SDK initialization example

1. **Objective-C**

   ```objective-c
     - (void)viewDidLoad {
   [super viewDidLoad];
   // Do any additional setup after loading the view.
   [UnityAds
     initialize:kDefaultGameId
     testMode:self.testMode
     initializationDelegate:self];
   }

   // Implement initialization callbacks to handle success or failure:
   #pragma mark : UnityAdsInitializationDelegate
   - (void)initializationComplete {
   NSLog(@" - UnityAdsInitializationDelegate initializationComplete" );
   // Pre-load an ad when initialization succeeds, so it is ready to show:
   [UnityAds load:@"Interstitial_iOS" loadDelegate:self];
   }

   - (void)initializationFailed:(UnityAdsInitializationError)error withMessage:(NSString *)message {
   NSLog(@" - UnityAdsInitializationDelegate initializationFailed with message: %@", message );
   }

   // Implement load callbacks to handle success or failure after initialization:
   #pragma mark: UnityAdsLoadDelegate
   - (void)unityAdsAdLoaded:(NSString *)placementId {
   NSLog(@" - UnityAdsLoadDelegate unityAdsAdLoaded %@", placementId);
   }

   - (void)unityAdsAdFailedToLoad:(NSString *)placementId
       withError:(UnityAdsLoadError)error
     withMessage:(NSString *)message {
   NSLog(@" - UnityAdsLoadDelegate unityAdsAdFailedToLoad %@", placementId);
   }
   ```

**Next steps**: To continue your implementation, refer to the [Implement interstitial ads in iOS](/monetization/sdk-integration/ios-sdk/interstitial-ads.md) documentation.