Remote staff using Facebook are seen as the biggest security and productivity threat to mobile working, according to research.
Some 55 percent of IT directors see social networking as the biggest problem, and just under a third said mobile porn websites also presented a threat.
Mobile gaming is also an issue, the survey found, with eight percent of IT directors highlighting it as a security and productivity theat. Seven percent were concerned about mobile TV.
In the survey of 200 IT directors of large UK companies, conducted by Vanson Bourne, some 92 percent identified heightened security threats directly attributable to more staff working remotely. But nearly all said their company was increasing mobile working.
Alex Donnelly, UK portfolio manager at IT services firm Damovo, which commissioned the research, said: "Sophisticated mobile devices are becoming the de-facto tool of choice for business users, yet it is clear that this is also bringing a whole raft of security and productivity concerns
"Without properly provisioning and having an effective mobile device management strategy in place, organisations are going to incur increased support costs and risk losing the visibility and security they had created in the fixed desktop environment."
One of the dangers, he said, is that many workers use one mobile device for both business and personal use. As a result, 63 percent of IT directors admitted that they found enforcing mobile usage policies difficult. Nine in 10 called for better visibility of their employees' mobile usage.
The proliferation of different system is also a problem, with users left to handle their own security and upgrades. As a result, organisations are left with many different devices running different software versions with differing levels of protection.
Eight in 10 IT directors said they found it difficult to manage and secure their mobile phones when they were not purchased through or specified by the IT department.
The same amount said that inconsistent upgrade cycles were leading to increased mobile security and performance concerns. Nearly all said also their mobile devices should be decommissioned in a more secure manner, considering the increasing amounts of sensitive personal and business data on the devices.