Offline targeted advertising


Today, ads are in every corner of the internet. All you have to do is spend a minute searching for information on hair loss, and moments later you will see tons of offers to stop hair loss. Click the „Like” button in the article describing genetic tests and you will see the promotions associated with them. Online advertising reflects the information gathered about everything the goal is – you! – he liked what he was looking for and what he watched online, and such a „journal” of virtual life reflects you quite reliably.

There is no surprise in seeing ads based on your browsing history – at least not when you’re online. Now, however, we will have to get used to something that has never been seen before: targeted advertising displayed on the street, in a store or in our car.

It’s easy to track you

First, you need to know that you are counted. Store and mall owners want to know how many people pass the store and how many are entering. The people who pass the store are counted by cameras, motion sensors, and ground-mounted sensors. People who line up at the checkout at certain locations are counted to optimize the number of employees in the store.

Second, the way you move is also tracked. Your smartphone serves as a radio signal transmitter (beacon). By measuring signal strength at different access points, marketers can pinpoint your location to within a meter. This is called the „customer journey,” and this data is immensely valuable to anyone involved in marketing.

Third, salespeople try to find out as much as possible about you. General information, habits and interests can be read by analyzing your purchase history and data published on social media profiles (later in this article I will tell you how it happens). With a camera lens at your disposal, modern image recognition systems can indicate the gender and approximate age of the visitor.

Any spontaneous actions by customers are also recorded. For example, Intel’s AIM Suite technology can determine if someone looked at an offline (physical) ad, how many people there were, and how long they looked at the ad.

How marketers track and sell

One of the most popular and effective methods of tracking potential and existing customers is the use of wireless (Wi-Fi) networks.

The technology is quite intriguing: when searching for available networks, a Wi-Fi enabled device emits its own MAC address, which is a unique combination of characters selected by the manufacturer (if the device has a Wi-Fi module enabled, the search is performed continuously). By reading this address, you can track a specific person’s movements and get some information, such as which stores they enter or how often they visit the mall.

Mobile platform developers made it a bit difficult for marketers to use this method. Starting with iOS 8, Apple mobile devices periodically emit fake MAC addresses, thereby blurring their owners' tracks. A similar tactic is used in the case of Android platform 6.0 and higher and Windows 10.

Nevertheless, this approach does not guarantee protection. In 2016, researchers from several French universities proved that a device can be identified by other service data it emits when it searches for a network – not including the MAC address. During the experiment, the researchers managed to track almost half of the tested devices.

How can the owner of a mobile device be identified without a MAC address? When the smartphone searches for a Wi-Fi hotspot, it also broadcasts the SSIDs of already known networks (whatever networks it was connected to). This list allows you to associate the phone with a specific person. This will be the case, for example, when the device owner changes the default home Wi-Fi network name, configured by the router manufacturer or network provider, to something unique.

As noted in the aforementioned project, modern devices typically do not use these mechanisms due to privacy concerns. However, the technique works fine for older devices. Moreover, broadcasting SSID numbers is the only way to connect to a hidden network. Therefore, cautious users who have hidden the names of their home networks are actually more likely to be tracked in public places than others.

You don’t need to use any of these tricks if your device is already connected to the network. In this case, the gadget sends the real MAC address to the access point.

Someone might say that the MAC address distinguishes between devices but not users. It is true. However, when using the free internet, guests may be required to authorize online, e.g. with their social media account.

Is free Wi-Fi convenient? Yes. Does anyone read the terms of service to find out how information posted on social media is being used? Someone will say that such people exist, but does anyone know them? In this way, store owners usually receive information from the user’s profile, which is a valuable material for preparing targeted advertising and other marketing tricks.

What is happening with your data?

Let’s take a look at  Purple’s End User Privacy Policy , more specifically Wi-Fi data collection and analysis.

The list of collected data includes:

  • information from social media accounts and login details (e.g. e-mail address) used to connect to the network,
  • history of pages visited using wireless networks,
  • technical specifications of the visitor’s smartphone, including IMEI number and telephone number,
  • the location of the visitor in the mall.

Who and how can use data about visitors?

  • Place owners, who can view offers to promote products and services, and analyze how and by whom the property is being used.
  • Advertisers who may receive general visitor information for consumer analytics.
  • Third parties that may also use them to serve personalized ads.

In addition, when a data operator sells a business or part of its assets, the information gathered is reported to new management.

In the case of Purple, the operator anonymizes the collected information after 24 months by deleting all data that allows the identification of a specific person. However, it is not clear when this process begins: if the last visit to a given facility is the determinant, then by connecting to the local network you can constantly extend the life of your data on the operator’s servers.

It is formally possible to opt out of collecting such data. For example, the aforementioned Purple allows users to add the device’s MAC address to the list of addresses ignored by the system . However, in practice it is difficult to check companies that operate wherever you visit (or are going to go). Therefore, a better way is to turn off the Wi-Fi module in your device.

The enemy at rest

According to the latest information, there is one more tracking option which is based on the use of ultrasound and which is gaining more and more popularity among advertisers. This technology is based on a well-thought-out placement of ultrasonic beacons. People cannot hear the signal being broadcast, unlike a smartphone’s microphone which can send it to an app installed on the phone.

Ultrasound beacons can be physical – placed in shopping malls to track customer movements – or virtual. Ultrasonic signals added to a TV show soundtrack can measure the number of viewers, for example, while ultrasonic audio files used by the website can record and track visitors regardless of the platform.

While this sounds like a proposition for the distant future – or at least something that’s still experimental – ultrasound tracking has been around for some time now. The problem is we can’t hear them.

In April 2017, researchers at the Braunschweig University of Technology reported that they discovered more than 200 apps that track users with ultrasound. They also mentioned that the technology is being used by three commercial platforms: Shopkick, Lisnr, and SilverPush.

Moreover, researchers also discovered Shopkick’s operational ultrasonic beacons in several European malls.

Smile: you are in a hidden camera

In November 2016, an intelligent billboard  tracked the drivers of certain cars in Moscow. Whenever a BMW or Volvo car came within its reach, Synaps Labs' experimental billboard displayed ads for the new Jaguar SUV.

The computer vision system compares the image of an oncoming vehicle with the image in its database and – taking into account additional factors such as time of day or weather conditions – displays relevant advertisements.

Billboards, which are aimed at drivers of passing cars , first appeared in Australia two years ago: “Hey, white Evoque! It’s never too late for a crossover. This is the new Lexus.

Another method (also from Australia) was used in Porsche’s billboards , which was aimed not at competitors' car drivers, but at the brand’s drivers. The slogan on the screen was praising the drivers: „It’s so easy to spot you in the crowd.”

Vehicle traffic tracking is even easier than people tracking with license plates. Fortunately, advertisers have yet to find a way to make use of them.