With the growth of in-app advertising, viewability measurement has become a requirement for marketers who want metrics for, and transparency into, the viewability of their campaigns. Mobile app publishers who don’t maintain healthy viewability metrics may miss out on campaign budgets for which healthy in-view rates are a prerequisite.

Best Practices


Do not use overlays (such as close buttons) that cover the ad and that subsequently cover the ad creative. This will adversely affect your app’s in-view rates. For more details, refer to the ad format in question under the platform-specific integration section; for example, details about integrating banner ads on iOS are here.

Transparent Overlays

We strongly discourage the use of transparent overlays. If you are using transparent overlays:

  • Android: Overlays must have alpha = 0 set for each overlay view.
  • iOS: Overlays must have hidden = YES set for each overlay view.

Custom Implementations

The MoPub SDK, and therefore our viewability measurement partners, do not support custom implementations. In this case, implementations such as custom ad wrappers and custom caching for banners may lead to lower in-view rates.


All pixels in the ad container should be on the screen in their entirety. This means that no pixels should be cropped out by content, or render beyond the edge of the device screen. For more details, refer to ad format article in question under this Best Practices section; for example, best practices for banner ads are here.

Viewability FAQ

Do publishers need to have a direct relationship with any third-party viewability vendors to support viewability?

No, but refer to the next FAQ for reporting requirements.

Can I get reporting for my direct campaigns?

Advertisers can receive reporting on direct campaigns if they have a direct relationship with a third-party viewability vendor. In order to collect viewability measurement on your inventory, include the third-party measurement tag to the Direct Serve creatives in the MoPub UI. The following formats are supported for viewability measurement on Direct Serve campaigns:

  • Interstitial HTML, VAST XML, and VAST tags
  • Rewarded ad, VAST XML, and VAST tags
  • Banner/MREC HTML

Note that native and direct image upload formats are not supported.

Which demand sources are enabled for viewability measurement?

MoPub Marketplace and Direct Serve line items are eligible for viewability measurement.

  • For MoPub Marketplace, advertisers can collect viewability measurement if they respond with creatives that include measurement tags.

  • For Direct Serve line items, publishers who upload their own creatives can collect measurement if they set up creatives with measurement tags provided by a third-party measurement vendor. Refer to our line items documentation for details about Direct Serve line item types.

Note: Other demand sources (that is, mediated networks) may collect their own viewability measurement, but advertisers must work directly with those demand sources to collect that data.

Last updated August 28, 2021

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