Can shoppers be tracked via their phone MAC addresses?

Tracking shoppers via the signals broadcast by their mobile devices has been a very popular way for retailers to measure precise footfall in stores, mainly since the smart phone revolution really kicked off in the early 2010’s. However, in recent years this method of shopper tracking has become almost impossible to sustain. 

The reason for this is that the MAC addresses of mobile devices are now being heavily randomized by companies like Apple and Samsung to protect the privacy of their users. The “spoofing” of MAC addresses involves devices emitting a brand-new signal multiple times an hour to give inconsistent data to any other technologies trying to track a particular device. 

MAC stands for Media Access Control, and a MAC address is a unique identifier assigned to every network interface on a device, including Wi-Fi and Bluetooth. While it is still possible to record shoppers via their MAC addresses, the data could never be truly consistent given the randomization of these numbers. A shopper could be counted multiple times, giving the impression that it is more than one person. Also, while it is rare, some shoppers may enter a store without having a phone on their person, meaning they would be exempt from a store’s attempt to gather precise footfall. 

The most accurate way to track a shopper by MAC address is for an individual to manually sign in to a store’s Wi-Fi, giving consent to the retailer to use their data in the process. The signal would not give much data about the shopper, however. A retailer would not be able to see the identity, age, gender, or purchase preferences of this shopper. 

There are concerns in the public sphere of having personal devices tracked, where knowledge of the attempted tracking is not known or advertised. The lack of consent and potential misuse of data for targeted advertising, price discrimination, and similar unethical practices are some of the main public concerns. 

Brands like Apple and Samsung have put measures in place to protect their customers. Apple use Intelligent Tracking Prevention (ITP) and Samsung have updated all devices from their series 10 onwards with default enabled MAC randomization. 

This means that if a retailer tried to gather data on iPhone and Samsung users via MAC addresses, their data would have the potential to be extremely inaccurate. Taking North America for example, 52% of Americans use Apple phones and 28% are using Samsung. So, 80% of the overall shopper bases would effectively be immune to shopper tracking. 

There are and have always been alternatives to MAC Address tracking for retailers. This would include the likes of loyalty programmes to collect data on shoppers’ individual preferences and purchase history, customer feedback via surveys or forms, or by using visual analytics to gain insights in real time.

While tracking MAC addresses might seem like a relatively sensible and easy way to gather shopper data, it cannot be considered a truly reliable approach in the era of ITP and MAC randomization. There are of course, some ethical concerns by the shopping public, who would much rather the option of opting-in to allow their data to be tracked by a retailer. As there are much more consistent technologies for shopper tracking and profiling, retailers should ideally look elsewhere than rely on MAC addresses.