Apple has denied that its iPhones and 3G iPads have been secretly recording their owners' movements. In a website posting, the company said it had never tracked user location and had no plans to do so in future.

Security researchers claimed to have found a hidden file on the devices containing a record of everywhere they had been.Some users managed to extract the data and plot it on maps.

More than a week after the issue came to public attention, Apple released an online question and answer document.It said: "The iPhone is not logging your location. Rather, it's maintaining a database of Wi-Fi hotspots and cell towers around your current location, some of which may be located more than one hundred miles away from your iPhone, to help your iPhone rapidly and accurately calculate its location when requested."

The document also addresses the fact - as some users discovered - that data going back months and even years was being stored."It shouldn't. This is a bug, which we plan to fix shortly," said Apple.