Have you ever wondered what the cost of “free” is? If you own a phone, it might be information you’d rather keep a secret, as Norton explores just how much we’re trading off to save a few quid here and there.

A study into our online app downloading habits has revealed some interesting things, with Norton finding out we’re more than happy to let someone else access our otherwise private information all for the sake of getting an app for free.

It could be a game or an app that shows you quotes or plays a song, but apparently many of us are letting it happen, as the cost of free makes itself apparent with the accessing of your important data.

“In today’s connected world, mobile devices are more than mini computers in our pockets – they are digital warehouses storing our most personal moments and information, such as photos and videos, conversations with friends and family, health and fitness information, financial data and more,” said Norton’s Mark Gorrie.

“However most consumers unknowingly – sometimes even willingly – put personal information which resides on their mobile phones at risk, compromising their privacy.”

Using Norton’s own Mobile Insight tool, Gorrie and his team have scanned several Android apps before installation to find what vulnerabilities and privacy risks they might have, finding roughly one-third of apps access address book information and call history, while others go even further, digging out usernames, passwords, and messages.

Norton’s survey was conducted worldwide last year, with 695 users taking it in Australia. Out of these people, Norton found that most Australians (74 percent) were worried about securing their data, but a little over 50 percent in Australia (and less around the world) aren’t worried at all about getting a virus. Strangely, those that were concerned about getting a virus were also more willing to install an app that invade their privacy a little.

But what do you do if the apps you’re downloading are only available in a free incarnation, and the violations of your privacy are the only way to get them?

According to Norton, a quick read of the terms and permissions will help see if the privacy violation is worth the risk.

“Central to this issue is consumers who fail to read end-user license agreements or don’t necessarily understand what they’re agreeing to before downloading mobile apps,” said Gorrie. “Many users fail to understand how they may be compromising their own privacy when accepting app permissions.”

Alternatively, you can grab one of the many app scanners made for Android by the various internet security companies, and Symantec makes one of those, too, called Norton Mobile Security.

Apps that have these issues can be found all across the place, but generally the free apps with these issues are found in the entertainment area, and are likely not to be picked up by someone downloading them because we’re just not thinking about them. Information leaked from these apps can include the phone number, call logs, text messages, and in some extreme cases usernames and passwords, making this one of those things that should be checked before installed.

It’s worth noting that Android is the operating system where the majority of these infractions are taking place, with Apple’s iOS locking things down usually in the approval process, and little news of any damage Windows Phone apps can inflict. That said, it’s good to be alert of what apps are doing on any platform, so if you have any doubts, try to read up on what each app is doing, especially if the price tag is free.