A hidden feature of Apple's new iOS 8 operating system may make it harder for marketers to track phones using current technology.

When phones scan for wi-fi networks, they transmit a MAC address that contains a identifier unique to each phone. By tracking these MAC addresses, marketers can determine a phone's make and whether or not the user is a frequent visitor to the area or not. Based on this information, stores can send deals to repeat customers and tailor mobile marketing campaigns in other ways.

The new iOS 8 contains a change to this process – it automatically randomises the MAC address each time it searches for networks, meaning marketing companies will be unable to track user's patterns and habits. The change was pointed out by Swiss programmer Frederic Jacobs on his Twitter.

The move may be a way of increasing the need for companies to adopt Apple's own iBeacon technology, which uses Bluetooth as opposed to MAC address to track users movements and determine patterns. Apple is currently running an iBeacon pilot in its own stores as well as Starbucks locations, and iOS 8 features a number of features aimed at integrating iBeacons more smoothly into its functionality.

Interested in learning more about how proximity marketing and beacon technology is changing the face of retail and other industries? You can still register to attend our Making Sense event on the subject, held on 11 June. Attendance is free for brand representatives.