One such campaign for Audi, designed around the car marque's involvement in the Le Mans race, achieved a 36% completion rate, which Celtra reported was 80% higher than its automotive benchmark.
"We believe that this is the form that will eventually get the most traction on mobile devices because of the way that consumption of content works on mobile and the way users are using and interacting with content," Mihael Mikek, CEO and co-founder of Celtra, told Mobile Marketer.
"Snapchat proved this with their success," he added. "Right now, a number of other companies are trying to develop and catch up."
Earlier this year, Snapchat, the photo-sharing app, reported that vertical ads were viewed to the end nine times more frequently than horizontal ones and advised content producers to simply turn their cameras on their side to frame shots as they will appear on phones.
More recently, it teamed up with WPP Group, the advertising holding company, and the Daily Mail, the news title, to create Truffle Pig, a content agency that will test new marketing formats – especially vertical video.
The advent of video streaming apps such as Meerkat and Periscope have reinforced the need for marketers to have a vertical perspective for mobile devices.
The Audi campaign, however, was actually taken from a TV ad and cropped to fit in portrait mode while also being shortened from 30 to eight seconds.
Mikek reported that Celtra currently has 20 brands lined up to run vertical video ads using its technology and expects the trend to be embraced across the industry.
"Going forward, vertical video will be one of the main focuses," Mikek said. "In the next few months, we'll see many more brands doing it."
And the use of vertical video is not restricted to mobile.
Data sourced from Mobile Marketer; additional content by Warc staff