This is despite increasing investment in mobile advertising, and that 80% believe mobile has significantly increased the amount of data at their disposal.
The report by the Mobile Marketing Association and RadiumOne, based on interviews with more than 300 senior marketers, also found that two-thirds are not confident that they've identified the most critical signals in their customer's journey.
"The industry talks incessantly about the flood of new data being produced and this is certainly the case with mobile, as people do more things on them, but the simple truth is most marketers simply aren’t confident of exploiting it adequately," Craig Tuck, RadiumOne’s UK managing director, said.
The study also found that more than six in ten marketers are still not fully confident in their ability to find new profitable customers, and even if they were to find them, half aren't sure they can acquire new customers or re-engage lost ones.
Customer loyalty too is an issue, with 58% who aren't sure their re-engagement efforts will prevent customer churn.
"The industry needs to do more in helping them in three key areas: identifying the right consumer signals of interest, building accurate predictions and then activating these to increase ROI," Tuck said.
The most valuable data
When it comes to mobile branding, marketers find content sharing from apps (29%), mobile site visits (28%) and app installs (27%) provide the most valuable insights.
In terms of mobile direct response, marketers find said they get the most value from purchase data (38%), geo-location and bookmarked content (both 35%).
Tuck acknowledges that driving purchases on mobile has "historically been a challenge compared to desktop," so brands that want to increase mobile transactions should "focus on the in-app experience – from having a simple UI, easy-to-access content and sharing features, and an easy way to buy."