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# sourceAppStoreItemIdentifier

The App Store ID of the app that displays the ad.

```
var sourceAppStoreItemIdentifier: NSNumber { get set }
```

## Discussion

Set this property to the App Store item identifier of the app that’s displaying the ad.

If you’re using a development-signed build to display the ads and not an app from App Store during testing, use `0` as the item identifier.

---

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