Developers of fitness apps could sell personal information to advertisers

Many people are using smart phone apps to keep fit, lose weight or stay healthy, but those free apps come at a cost – your personal information.

Trying to stay in shape has gone high tech, whether someone is watching their diet, waistline or emotions – there's a phone or tablet app that promises to help.

"When you get more exact with things that can track your pulse, your heart rate, your body temperature … That's information where you can start having a discussion with your doctor about it," Tech expert Bridget Carey said.

But when you're using health and fitness apps to accomplish your goals, there is someone else between you and your doctors – the software developers and people marketing those apps.

"They have your personal information," said Kim Gough, of Privacy Rights Clearinghouse. "Maybe they know how far you ran; how many calories you took that day."

And maybe they keep track of those goals and accomplishments and share them with others. It has some asking, "What's the big deal? The apps are free."

"You have to make money somehow," Gough said. "Some of these free applications will then sell your information to 3rd party advertisers."

Gough said San Diego-based Privacy Rights Clearinghouse sampled nearly 50 popular health and fitness apps. Do people who download and use these apps know their personal information could be collected and sold?

"I think the majority of them don't have a clear understanding of what the app is doing in terms of their personal data," Gough said.

The information they gather may lead to nothing more than you getting an ad for tennis shoes or health food. The bottom line for privacy proponents, though? The people behind these apps should disclose what they're doing with your personal information.

"I think we'd like to see the developers of the apps just have a little more transparency and say, ‘We're gathering this data on you, and this is what we're doing with it,'" Gough said.

The privacy rights study found free apps are more likely to share personal information than paid apps.

Experts suggest limiting the amount of personal information consumers share. They also recommend deleting an app when you stop using it.