Open Measurement is an IAB standard that allows publishers to use third-party viewability providers to verify impressions and click measurements. Google Mobile Ads SDK supports Open Measurement starting with version 7.43.0 . This and later versions of Google Mobile Ads SDK integrates with the [Open Measurement (OM) SDK](https://iabtechlab.com/standards/open-measurement-sdk/) to enable third-party viewability measurement. Google Mobile Ads SDK supports OM SDK version 1.4. ## Prerequisites \* Google Mobile Ads SDK 7.43.0 or higher. - [Set up Google Mobile Ads SDK](https://developers.google.com/ad-manager/mobile-ads-sdk/ios/quick-start.md.txt). - A configured [viewability provider](https://support.google.com/admanager/answer/9025968#configure-a-viewability-provider) assigned to your line item. ## Implement Open Measurement Google Mobile Ads SDK automatically implements Open Measurement using **"Google"** as the Open Measurement partner name for all ads served using the Google Mobile Ads SDK. To use a third-party viewability provider, configure it in the Ad Manager UI, and configure your line items to use that viewability provider. For more details, see [Configure a mobile app viewability provider](https://support.google.com/admanager/answer/9025968). > [!NOTE] > **Note:** Custom native ad formats that don't render a video asset require a custom Open Measurement integration. For more information, see [Display-type Custom Native Ad Formats and Open Measurement](https://developers.google.com/ad-manager/mobile-ads-sdk/ios/custom-native-omid.md.txt). ## Ensure that transparent overlays are non-obstructing For an ad to not be considered blocked, the view that is obscuring the ad must have one of these settings: - `alpha = 0`, or, - `isHidden = TRUE` It doesn't matter if the obscuring view has a transparent background, the view's alpha and visibility values are what determine whether the view is blocking your ad. If the Open Measurement SDK detects an obstruction over the ad, it could impact whether a viewability provider considers the impression viewable. To fix this, set your view's alpha to `0` or set `isHidden` to `TRUE`. ## Troubleshooting Be aware of the following when implementing Open Measurement: - You must check with the mediation partner to learn if they support Open Measurement for ads they render. - Ads that are obscured by overlaying views might not register viewability measurements. For more information, refer to [Ensure that transparent overlays are non-obstructing](https://developers.google.com/ad-manager/mobile-ads-sdk/ios/open-measurement#obstructing). - On [test devices](https://developers.google.com/ad-manager/mobile-ads-sdk/ios/test-ads.md.txt#enable_test_devices), including the iOS simulator, the **Test Ad** label is detected as non-obstructing to the ad view.