How mobile app interstitials work

Interstitials are full-page ad units served between screens during mobile app navigation. They present a user with full-screen app experiences at natural app transition points such as launch, video pre-roll, or game level load.
Interstitial ads:

• Are perfect for brands: The large size presents an ideal canvas for storytelling, making them a highly attractive format for brand advertisers.
• Are highly engaging: Because of their size, use of rich media, and attractiveness to premium brands, interstitials drive high user engagement. This, in turn, generates high click-through and conversion rates.
• Are in demand: Interstitials are constantly cited as the most desirable ad format by both brand and performance mobile advertisers.
• Increase ad diversity: Integrating new ad formats is one way publishers can deliver a diverse ad experience to their users, thus minimizing "banner blindness" and increasing overall ad engagement.

For more detailed information and examples, refer to the developer's guide (Android or iOS).

Benefits of interstitials on Ad Exchange

Ad Exchange mobile sellers can request interstitials from their apps directly or through Google Ad Manager by simply trafficking Ad Exchange code for the interstitial. This feature is available as an additional ad size and can easily be implemented on all publisher properties. Ad Exchange interstitials:

• Provide strong revenue returns: Interstitials historically have higher CPMs than banner ads.
• Use diverse demand sources: The Ad Exchange allows you to tap into interstitial demand from all the major DSPs and agency trading desks, as well as over two million advertisers through Google Ads.
• Provide creative variety: The Ad Exchange supports multiple creatives within the interstitial format, including full-page rich media units, dynamically created app promotion units, and standard banners against an opaque background. This variety drives up auction pressure, resulting in higher CPMs.

Get started with trafficking interstitials

In Ad Manager, interstitial ads can be trafficked using the following sizes:

• 1024x768 (landscape) or 768x1024 (portrait) for tablets
• 320x480 (portrait) or 480x320 (landscape) for mobile devices

When trafficking interstitials on Ad Exchange, please keep the following in mind:

• Unlike static ad sizes, whose requests are based on a fixed box size, the size of interstitial requests depends on an interstitial format request as well as the screen size of the device requesting the ad.

  Here's the process:

  1. Ad Exchange detects the screen size and sends the width and height of the entire screen to the buyer as the requested size.
  2. The buyer can then respond with any size creative as long as it falls within 50% of the screen width and 40% of the screen height

  Example

  1. Ad Exchange detects a 320x480 screen size on a mobile device and requests an interstitial ad.
  2. An interstitial creative ranged from 160x192 to 320x480 can be returned from Ad Exchange. As 320x480 is a supported interstitial size in Ad Manager and falls within the range, 320x480 interstitials can be returned.
• Interstitials are not trafficked differently than other ad units. Publishers can treat an interstitial ad request like any other size. Keep in mind that interstitials can only be called for ad units that occupy the entire screen: in other words, a takeover.
• Links must use admob.opener.openUrl() or mraid.open() to ensure that they open in a new window rather than in the interstitial view itself.

• Interstitials must show a close button. Both video and non-video interstitials can show the close button either from the start, or following a 5-second delay. Non-video interstitials which are engaging and/or interactive can show the close button with a 5-second delay timer.

• To see how your interstitials are performing, select the Creative size (delivered) dimension in a report. The report will display "Interstitial" when the ad call is an interstitial ad in a mobile device.
• Only interstitials booked via direct campaigns in Google Ad Manager can be automatically closed. Interstitials served via dynamic allocation (for example, Ad Exchange, AdSense, or Google AdMob) can only be dismissed by the user.