As Facebook hits the one billion user mark, a new report reveals the changing habits of individuals on the site, which could have the company rushing to catch up with its audience.

A study by Macquarie Research indicates that while Facebook engagement remains strong, a significant shift towards mobile means the social network needs to move faster with its mobile ad plans, if it’s to remain profitable. More than half (56%) of the 559 15- to 25-year-olds surveyed access Facebook from a mobile device, compared to just 24% last year. According to Macquarie, that figure will reach 70% by this time next year.

The study also revealed that people are becoming more passive on Facebook, preferring to browse other people’s content than update their own status. Men are more likely to respond to their friends’ status updates than women (33% to 28%), while women are more likely to share content than men (20% to 17%).

These are still low engagement figures, which poses the question: is Facebook losing its appeal? According to a Reuters poll released in June, yes. However, with the shift towards mobile gaining traction, could it simply be a case of accessibility, rectified by making Facebook apps and the mobile site more intuitive and user-friendly?