Google found a way against those app download interstitial — that pushes the users to download their mobile app. The search giant announced that, as of November 1st, sites with intrusive app download interstitials will be penalized
“After November 1, mobile web pages that show an app install interstitial that hides a significant amount of content on the transition from the search result page, will no longer be considered mobile-friendly.”
If the sites are not considered as mobile friendly, it will have a significant impact on its organic search traffic. As google has already stated to support more mobile friendly sites in the mobile search.
Google has updated its mobile-friendly testing tool. As well, the Mobile Usability report in Search Console warns if there are large app download interstitials.
Rather than using app download interstitials, Google reminds that browsers promote apps in ways that are more user-friendly.
It’s evident that, when google issues a recommendation its often wise to follow it.