Fingerprinting is a technique used by companies to uniquely identify a browser or device in order to track its online activities.
Forms of fingerprinting
Device fingerprints are the strings of numbers and letters identifying a mobile device. The apps on your phone or tablet have access to this fingerprint, and they may use it to combine all the user activities on these apps with a unique user ID to deliver interest-based advertising, for instance.
The term of browser fingerprinting refers to the collection of data from a web browser to identify and track users. It relies on information sent by the browser itself, such as timezone, plugins installed, cookies preferences, IP address and user-agent (containing among other things the operating system type and version).
When the user visits a website, an advertising company may gather the information listed above to fingerprint the visitor and determine if they have already been surfing on this site (or a third-party website where they may also operate). This way, the user’s behavior can be tracked across websites to create an advertising profile to target ads inferred from their browsing. This tracking is different, but can be combined with the tracking cookies installed in your browser. Cookies can be easily managed and deleted in your browser settings, while blocking fingerprinting might be a harder task.
How to prevent this tracking?
It is nearly impossible to entirely block all forms of fingerprinting There are however some measures that can be taken to limit it. For instance, some browser add-ons are known for restricting some kinds of tracking like Canvas fingerprinting. To disable device fingerprinting, the solution could be device spoofing, although it isn’t generally easy to set up on your phone.
Restore Privacy - Browser Fingerprinting – Explanation, Tests, and Solutions
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Adjust - Device ID meaning
TechnologyCatch - An add-on that prevents Canvas Fingerprinting