For Google SEO, interstitial ads and mobile websites do not make good bedfellows!
Google has started a campaign to gradually force webmasters to optimise their website for mobile devices. Among the bastions that should fall are interstitial ads...
What are interstitial ads?
For advertisers, interstitial ads are an ideal advertising format. When someone visits a website, he/she gets to see this interstitial ad as an intermediate page or overlay above the actual content of the website. Therefore, the visitor is forced to close the ad before he can see the actual content of the page.
This is a blessing for advertisers, because they know for sure that the visitor has at least seen the ad. As for the visitor, he is probably not that happy with the interstitial ad. He sees the ad more as an obstacle that prevents him from accessing the site, which will most probably also irritate him.
Especially mobile websites that want users to download their native app, sign up for their newsletter, etc. use interstitial ads. However, Google recommends not to encourage such practice. Worse yet, using interstitial ads may have a negative impact on the underlying page’s Google SEO, as you can read on the Marketing Land website.
Which alternatives are better for Google?
On Google’s Developers website, experts recommend to replace interstitial ads for websites that are visited using mobile devices with a simple inline banner (either native banners like the SmartApp Banners for Safari or ordinary HTML banners that point to the page in the app store).
For Android apps, Google recommends to use app indexing. When indexed content of your app is relevant for a certain search, Google will also add an Install button next to the search results. The user can then download the app and is instantly redirected to that specific page.
You should definitely consider this advice. Not only will it help you boost your SEO, but it will also prevent you from irritating users!