A consumer watchdog report released Tuesday showed mobile devices accounted for 61 per cent of internet connections over the three months to December 31, but only six per cent of data downloads.
Instead, fixed line broadband dominated data download volumes at 91 per cent - from just 18 per cent of connections.
"This report provides a clear indication that while consumers are most often using their phones to access the internet, when downloading significant content they currently favour fixed line connections," ACCC commissioner Cristina Cifuentes said.
"The volume of data downloaded is expected to grow exponentially as the result of the increased usage of content streaming services such as Netflix, social media such as Facebook, and applications including online gaming that continue to incorporate content-rich and video components."
But the imbalance could be short-lived, with super fast 5G connections just around the corner.
"The imminent arrival of 5G products and services will likely support even greater increases in the volume of data downloaded via mobile handsets and wireless broadband access technologies," the report said.
Other data in the report included the most popular speed tier for fixed line and wireless broadband is less than 24 megabits per second.
This speed accounted for 61 per cent of all fixed line/wired and wireless broadband, followed by the 24 Mbps to less than 50 Mbps at 25 per cent.