• by Wendy Davis  @wendyndavis, July 5, 2013

Despite Apple's privacy rules for app developers, many iPhone apps still access the phones' unique device identifiers.

A study by University of California, San Diego researchers recently found that 48% of apps accessed the unique device identifiers -- 40-character alphanumeric strings. Conducted last year, the study involved examining 90,000 jail-broken iPhones that installed the analytics app Protect My Privacy. (That app, which allows researchers to see how other apps are collecting data, can only be used on phones that have been jail-broken.)

The study also found that 13% of apps accessed location data, and 6% gleaned information about users' contacts.

Apple officially told app developers to stop accessing the unique identifiers by May 1. But recent tests by the study's authors found that around 40% of apps were still accessing the unique device identifers, researcher Malcolm Hall told MIT Tech Review.

Apple's new iOS 7 operating system will block app developers from accessing unique device identifiers. The new operating system also will prevent developers from tracking people via their Media Access Control addresses -- permanent identifiers assigned to any device that is capable of connecting to the Web.

Apple informed app developers that want to monetize their services' mobile ad networks to use Apple's “Ad Identifier.” In contrast to unique device identifiers, which consumers can change only by performing a factory reset, consumers can easily clear and reset their ad identifiers.

"Smartphone with Lock" photo from Shutterstock.