Apple's iOS 4 platform keeps an archive of user data which can be transferred to PCs and migrated over devices, according to researchers.
Pete Warden and Alasdair Allan reported that iPhone and 3G iPads running iOS 4 keep locally stored file records on where the device has been at various points.
The archive is copied to a Mac or PC when the iPhone is synched over iTunes, and can be migrated when data is copied to new devices.
The researchers have created an application which allows users to view the location data on OS X systems, but warned that the data archives can be found within the OS X Mobilesync directory.
The purpose of the data collection is unclear, and there is no evidence that the location information is being transmitted beyond the device and synched computer, but the researchers noted that the ease with which the files can be accessed could pose a privacy risk.
"The most immediate problem is that this data is stored in an easily readable form on your machine," wrote Warden and Allan. "Any other program you run, or any user with access to your machine, can look through it."
To help secure the information, the researchers advising people to activate the 'encrypt iPhone backup' option within iTunes.
Peter Eckersley, a senior staff attorney for the Electronic Frontier Foundation, told V3.co.uk that Apple is hardly alone in having potential privacy issues.
Location tracking services have exploded in recent months, and the industry as a whole has had difficulty figuring out how to keep this data secure.
"This story will be part of a gradual process of realisation," said Eckersley. "Right now none of these companies have an answer."
V3.co.uk contacted Apple for comment on the report, but the company had not responded at the time of publication.
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