Digital services are deeply embedded in the daily lives of millions of internet users. Living without the use of apps, whether on smartphones or PCs, is almost unimaginable nowadays.
But this raises the question: Where are we leaving our digital footprints in the form of location data, what are these pieces of information used for, and what does this mean for privacy?
Location data provides information about when a person or device is at a certain place. For instance, mobile network operators can determine a user's approximate location by connecting to a cell tower.
Providers use mobile cells, which are areas covered by a cell tower or base station. Each cell has a unique ID used for location determination.
Movement data, on the other hand, not only provides the exact location of a person but also shows how they reached that location or the route they took.
Almost all smartphones, smartwatches, and other mobile devices today have GPS (Global Positioning System), a global positioning system that calculates the exact position using satellite signals and their distance to the device.
When users download apps or programs, they are often asked to allow access to their location data. To enjoy full convenience or even to use the service at all, users often unknowingly agree, allowing the program or device manufacturer full access to their data. The manufacturer is legally required to inform the user about data processing, its purposes, and the types of data collected, but privacy policies of many apps are often complex and lengthy. By simply clicking agree, users often grant providers extensive rights to track their location always or during app usage, such as weather apps, Google Maps, or telephony apps. Especially with free apps, data is often shared for commercial purposes with third parties.
Processing location or movement data creates detailed movement profiles for each individual, revealing where a person works, what they do on their way to work, and how they spend their leisure time. Together with data collected via cookies on websites or location information voluntarily shared by users on social media, this data can be aggregated to create precise profiles of a person's preferences, health status, or activities.
For example, when a user uses Google Maps for navigation, they share their location data with Google. Google creates detailed movement profiles, knowing if the user stops at their favorite café for a morning coffee on the way to work. This coffee is paid for with a credit card, earning Payback points. During the lunch break, the user browses various online shops, agreeing to the use of cookies and analytics tools on those sites. By analyzing collected data from various sources, companies can identify user behavior patterns and preferences, allowing them to display personalized ads on websites or better tailor their product offerings to the market.
So far, so good – but how is this data monetized? This is where data brokers come into play. Data brokers receive usable data from mobile devices or apps, ad networks, telecommunications providers, or from Software Development Kits (SDKs) provided to app developers. SDKs are code that determines which ad campaigns lead to app installations or which user interactions (clicks, views) a user performs in an app. Billions of data points from various sources are collected by data brokers and then offered for sale to the advertising industry or used for market analysis. The data trade has become a very significant economic sector for many companies, with global revenues in the hundreds of billions.
Big Data applications play a special role here, as they can analyze and interpret an enormous volume of data, often unstructured, from various sources in a very short time. This is used by the advertising industry for personalized advertising or customer behavior analysis. Other use cases can be found in healthcare, the financial sector, and energy supply.