iPhone or spy-phone?

Security researchers have discovered that Apple's iPhone and iPad keep a minute-by-minute track of their users' geographical location.

The researchers say iPhone synchronizes the information through the digital media player iTunes every time it finds a wireless network without the owners' consent, The Wall Street Journal reported on Friday.

The American Civil Liberties Union says the issue raises security concerns.

The researchers have also revealed that Android phones, which use Google's mobile operating system, store users' geographic information in a very similar way.

Google says it has been collecting location data from its Android smartphones, but it has provided users with the option to turn off that feature. However, Apple has not commented on the matter so far.

The new revelation has sparked criticism among digital rights activists and is an eye-opener for many Apple customers.

Apple's general counsel, Bruce Sewall, disclosed in a letter to the US Congress last year that the information is collected anonymously and the devices give users controls for disabling the location features, adding that Apple stores the location information in a database only accessible to the company.