GLOBAL: Consumers who watch video on their mobile screens are not deterred by length as a new study shows one third of them daily watching content lasting five minutes or more.

The Interactive Advertising Bureau (IAB) polled 200 mobile-video-watching consumers in each of 24 countries for its report Mobile Video Usage: A Global Perspective.

This found that 36% watched long-form videos at least once every day, with respondents in Turkey, Finland, China, Russia and Singapore emerging as particularly frequent viewers.

But whether short or long or in-between, substantial numbers of video viewers reported that their video consumption on smartphones had increased year-on-year, with the most prominent upticks being seen in the US (50%), Canada (42%), New Zealand (42%), South Africa (42%), and the UK (40%).

This trend is also impacting traditional television viewing across the board, the IAB said, with consumers in China (37%) and Singapore (35%) reporting the highest incidence of watching less TV due to streaming more on mobile.

Further, even when mobile video viewers do watch traditional television, around one fifth (22%) do so while simultaneously watching video on their phones.

"The popularity of digital video is evident across small screens the world over," said Anna Bager, svp/mobile & video, IAB. "The fact that people are not only watching short snippets of programming, but committing to longer form content on their phones, opens doors for brands to be part of this impressive mobile engagement."

But she also pointed to another new challenge for marketers: "How do you grab a viewer's attention when it's divided between two simultaneous video feeds?"

Across all countries by far the most common way to discover digital video to view on phones was through YouTube (62%), followed by social media platforms (33%) and search results (20%).

Advertising (14%) was the least popular, although it did have a greater influence in the US (22%) and Canada (18%).

More than a quarter (28%) of respondents reported that they often saw ads on mobile video that they had already seen on TV, but the IAB pointed out that most expressed interest in any kind of tailored ad versus "I prefer no tailoring of ads at all".

This, it said, points to the importance of ads being relevant to the content of the video being watched.

Data sourced from IAB; additional content by Warc staff