The researchers found that the sensitive data is stored unencrypted and unprotected, and that it is stored on every PC you sync your iOS device with. The data can be easily accessed and provides data on everywhere your 3G iOS device has been .

Storms cautions, "We already have a third party app available that can read and plot the data. It would be pretty easy for a Trojan app to do exactly the same thing. I can imagine a lot of law enforcement applications that would not exactly thrill users."

Fred Touchette, senior security analyst at , says, "Imagine what evildoers could do with that info; they could easily recognize daily patterns and know how long you'll be away from your home or office. There is also a possibility such information can be accessed remotely with custom crafted malware, and then sold on the black market much like cyber criminals currently sell credit card information."

Apple has some explaining to do. There must be a reason the data is logged in the first place, and stored on your iOS device. It is hard to imagine a legitimate use, though, that would excuse breaching user privacy in this way.