Editor's note: Jon Brand is senior vice president in marketing effectiveness at research company GfK. 

Even before the COVID-19 pandemic, mobile media were playing an increasingly powerful role in consumers’ lives – and, not surprisingly, in media budgets. In the U.S., mobile media now exceeds one-third of all media spending and a 2021 GfK study shows that, among common digital technologies, smartphones are most trusted and relied on by U.S. consumers. 

Throughout the day, consumers return to those small(er) smartphone screens again and again – for an average of 63 interactions every day, according to Leftronic. No other technology or platform can claim this kind of repeated exposure and 24/7 influence. 

But when it comes to advertising, smartphones – and mobile devices generally – are too often playing second fiddle to “traditional” technologies: TVs and PCs. There has been little effort to truly understand mobile ads in their own context and environment. Evaluative approaches are not as robust as traditional TV techniques – and systems are often inconsistent with past testing, leaving management confused on how to interpret.

The truth is that little is actually spent on digital ad testing in general; simplistic approaches with few diagnostics provide a minimum of information or inspiration to drive stronger creative. And when it comes to mobile ads, the commitment to evaluating and refining is even weaker. Despite the impressive growth in streaming over mobile devices, they simply are not given their due.

We know that consumers interact with mobile devices in unique and specific ways – vastly different from a TV or PC environment. Screen size has a huge effect on how people engage with and experience advertising; small pictures and uncertain sound quality create special demands on creative. Frequently, mobile media are viewed in the context of other activities – watching TV, working or...