In the world of video advertising screen size doesn't matter: study

In a recent global survey, the majority of those surveyed agreed watching video on mobile devices was convenient. Increasingly the cost of producing that video content is being paid for by advertising, with advertisers also shifting their focus to mobile. However do those devices deliver a less engaging viewing experience? Four biometric studies show that nowadays, screen size doesn’t matter. A screen is a screen.

We found that what matters isn’t the size of the screen, but how big it appears on the retina. If you hold a mobile phone close to your eye, it can appear as big as a large flat-screen TV. We also found that small screens can be just as exciting to watch, because we hold them in our hands.

These results were surprising, because previous research had found small screens were hard to see, and not very exciting to watch. But these studies had not allowed people to sit closer to smaller screens or hold them in their hands. And before the release of Apple’s retina screens, content producers and advertisers were advised to create special low-res versions for viewing on a mobile screen.

Our biometric studies investigated whether video ads seen on mobile screens were less memorable and engaging, compared to TV and computer screens.

What we found

We invited participants to come into our lab and watch two 15-minute programs, with commercials, on different types of screens. After watching the content, participants answered questions about the quality of their viewing experience, and how many of the advertised brands they could remember seeing.

Participants were randomly assigned to different screens. For example, in the first study, one third watched a flat-screen TV, one third watched a personal computer screen, and one third watched a small mobile screen.

Instead of controlling viewing distance by using, for example, a chin rest, we allowed our participants watch from as close as they liked. In addition, participants viewing the smaller mobile screens held them in their hands. We measured viewing distance with a side-on camera to calculate apparent screen size.

In the second study we also measured viewing excitement using skin conductance. The flow (conductance) of a micro electric current across the skin is increased by moisture from special sweat glands wired to the body’s sympathetic (fight or flight response) nervous system. We measured skin conductance by attaching electrodes to each participant’s non-dominant hand (the one that wasn’t holding the mobile phone).

Without controlling for viewing distance, there were no differences in brand recall across screens. However, recall was related to viewing distance. If the screen appeared large, the advertised brands were more likely to be remembered, whether the screen was a mobile phone or a tablet, a TV or a computer.

The skin conductance results showed mobile phone participants experienced the same levels of excitement as participants who watched the larger screens.

The effect of holding a mobile phone on excitement was stronger than the effect of viewing distance. The effect of distance was clearest for the desktop personal computer, which was not held in the hand.

Interestingly, the participants who saw the mobile screens rated their viewing quality higher than the participants who watched a TV or a computer. This may have been a novelty effect (many were watching an Apple retina screen for the first time) but it adds to our argument that smaller screens can deliver an equally good experience.

The mobile phone is the most convenient screen we have. Kai Pfaffenbach/Reuters

What does this mean for us?

These results explain why many of us don’t turn on the TV set to watch YouTube videos if we have a mobile phone in our hands. The mobile phone is not only the most convenient screen we have, it is also an equally good screen. Video content seen on a mobile phone is just as exciting, enjoyable, and memorable.

Of course, nothing is as immersive as a huge IMAX screen. But people with large flat-screen TVs generally watch them from far enough away that they don’t need to move their head to see every corner of the screen. Seen from that far away, the size of a flat-screen TV is easy to replicate by holding a mobile phone screen close to your eyes.

Holding a mobile phone is a muscular activity that increases bodily arousal, and this may explain why mobile phones were just as exciting as other screens. But future studies may find that this effect is intensified when the phone is actually the participant’s personal and private property.

These findings suggest that video content producers and advertisers do not have to worry about viewing on mobile devices. Viewing on these devices can be just as effective as viewing on any other screen. And with today’s retina screens, there is little need to adapt content for viewing on a small mobile screen.