When we initially learned about AdWords enhanced campaigns, one of our biggest concerns was the inability to cleanly target only mobile phone users with a campaign. We regularly see significant differences between how mobile and desktop audiences interact with our clients’ ads, and in the pre-enhanced campaign world, segregating audiences into different campaigns by device offered us a convenient and effective way to optimize performance around how well our clients could monetize traffic from users on different devices. Since enhanced campaigns, by default, would be set to show ads to users on all devices, our clients were concerned that a flood of new competitors (who weren’t previously advertising to mobile users) vying for placement on mobile search results pages would drive up mobile click costs.
To preserve the gains that we made by creating device-targeted legacy campaigns, we utilized low keyword bids and a high campaign mobile bid adjustment to try and recreate mobile-only legacy campaigns within the new enhanced campaign structure.
Since transitioning all of our clients to enhanced campaigns, we have had varying degrees of success restricting ad delivery to mobile devices only. For some of our clients, AdWords traffic volume from desktop users has been as low as 1% in campaigns intended for mobile users, while in others, the percentage is as high as 20%, with the portion of impressions served to desktop users between 1% and 15%. So far, the difference seems to be keyword bids. With the campaign-level mobile bid adjustment limited to 300%, we are finding that even some significantly reduced keyword bids aren’t low enough to disqualify ads from showing on desktop search results pages.
Despite an anticipated increase in competition for ad placement on mobile devices, our clients haven’t experienced significant increases in mobile click costs, or lower ad positions. For consistent ad position, we’ve seen an average cost-per-click increase of between 4% and 6%.