On the mobile Web, app install pop-ups can interfere with your experience. Google is taking steps to make sure they don’t, and has begun testing half-page ads to prompt you to install an app.
The change of heart comes as we edge away from ads and towards content; Google says full-page prompts block too much of the content you’re there to see.
Google says after November 1, webpages that show full-page app install interstitials after clicking on results in mobile search will no longer be considered mobile friendly. Other full-page ads won’t be affected by this change.
It’s a small change, but may be beneficial to everyone. If you’ve ever angrily dismissed a pop-up because you just wanted to see content, this might be the happy medium everyone can agree on. A half-page ad still allows the user to see information, but also lets them think a bit longer about whether or not a native app might be better for them in the future.
➤ Mobile-friendly web pages using app banners [Google]