IPHONE MANUFACTURER APPLE has told the US Congress that the iPhone’s log of nearby WiFi hot spots and cell towers is meant to improve service, and is not an attempt to stalk customers.

Apple emphasized, as it had previously, that any data it receives about the locations of the hot spots and cell towers is anonymous, and not tied to a particular user.

The company told a US Senate subcommittee it was building a database of locations in order to optimise services like mobile mapping. Using GPS signals can take several minutes to locate a phone, while using the location of known hot spots and cell towers stored directly on the phone can be quicker.

Apple vice-president Guy Tribble will offer further testimony to the subcommittee later today. A Google executive, Alan Davidson, is also scheduled to appear.

Congress is demanding details from smartphone companies about their tracking practices, after researchers revealed last month that iPhones and Android phones themselves were secretly keeping track of users’ locations.

Apple and Google say they only record the location of WiFi hot spots and cell towers to improve service, and tracking can be turned off.

Apple said a “bug” caused the iPhone to keep location data even when tracking was disabled, and has issued an updated version of its iOS operating system to disable the tracking feature.

Additional reporting by Gavan Reilly