What are Mobile Pop Ads

Definition

A pop-under is a type of online advertisement that appears behind a mobile browser tab without interrupting content. Pop-unders only become visible once a user has closed the top browser tab, or are browsing through browser tabs. Mobile pop-unders are the same size as the mobile browser, usually 320 x 480px (up to 960 x 1440).

Compared to other ad formats

Pop-unders have a lot of potential due to their size and user attention. They outperform standard mobile banner ads exponentially on click-through rates (CTR), with very high user engagement and/or interaction since the user has to close the ad manually. However, as mobile ad blocking software becomes increasingly popular, inventory may be hard to come by.

What makes pop unders special

Designed to be less intrusive than pop-up ads, pop-under advertisements does not interrupt a user’s content experience. Due to the fact that pop-unders open in separate mobile browser tabs, it is often difficult for users to establish which site generated the ad. This reduces potential negative association.

Ad-Pixel Size

Mobile Pop-unders: Full size of mobile browser page. Usually 320 x 480px (up to 960 x 1440)

Optimal File Size

On the web, smaller is always better when it comes to file sizes, even with today’s fast connections and cheap data. For pop-under ads, files should be kept around 40KB, but no larger than 50KB, including HTML based ads.

File types:

GIF: Animation, transparency, size PNG: better transparency, size, newer format JPG: Photo, artwork HTML5: Video content.

What’s important for advertiser

High visibility, less intrusive, lucrative ROI potential

Mobile pop-under ads benefit from high visibility due to size and user attention. These ads have relatively high CPM rates compared to mobile banners and redirects, but are also more costly. However, they provide lucrative ROI potential, which makes them attractive. It should be noted that pop-unders run the risk of being exceptionally annoying to users, and thus should only be displayed to users once per day. The prevalence of mobile ad blocking software may also decrease their effectiveness. Pop-unders are great for app installs, trials, lead generation, and mobile content offers (pin submits).

For creatives, the size of pop-unders give a fair amount of room to design high impact ads. However, the less is more rule still applies and ad should be uncluttered, using fast-loading, simple images.

What’s important for website owners

High CPM rates, high visibility, less intrusive

Mobile pop-under ads have very high CPM rates, making them potentially high earners. This is due to their high visibility and exponentially higher click-through rates compared to standard mobile banner ads. In fact, because pop-under ads don’t encroach on current mobile site real-estate and/or advertising, they are essentially ‘bonus’ earners. However, as with desktop pop-unders, site owners should be very careful about what kind of pop-under ads they allow, since they also come with a fair risk of negative association. Ad blocking software may also impede earning potential.