Android offers its users the ability to customize the system to unsuspected extremes, especially when apps come into play that allow us to change launcher, play with icon packs and with a thousand and one factors that can make our mobile something “unique”. Although precisely this feature may lead to different calculations to assign a DNI to our mobile, unless we change one of these factors in order to vary the identifier.
This technique is known as a “fingerprint”, and just as our Android can be identified by the camera, there is a (a little far-fetched) method that can allow recognize our phone among millions based on our desktop background. Our wallpaper. And everything can be done through a simple API offered by Android itself and which can be used by other applications that we install on the system.
Your wallpaper can betray you, but not much
While this can be treated as an issue for our privacy, the truth is that this system does not throw away personal information about us unless we have uploaded a photo of a family member, a friend or even ourselves as a wallpaper. We’re just talking about a system that allows you to establish a unique code to be able to recognize our mobile among many others. A pattern that can be changed without problem on the other hand.
It turns out that in Android there is an API built into Android that offers certain information about our desktop background. Specifically, we are talking about the WallpaperManager class associated with Android 2, but this changed with the arrival of Android 8.1. The “vulnerability” or risk of exposure to informati on has been corrected to some extent. And a method has been developed to get information about our wallpaper.
By using the getWallpaperColors function on Android it is possible to extract the three main colors of our wallpaper, but by using different advanced algorithms it is possible to go much further. So once this complex process has been completed it is possible to create a unique 256-bit identifier for our mobile phone based on our wallpaper. It makes sense to think that this number is the same as that of another mobile that uses the same wallpaper, and it is true. Thus, the identifier can only be “critical” when we use our own photographs, since theoretically only we have them.
Thanks to a series of complex algorithms, it is possible to create a DNI from your wallpaper.
Thus, it is possible to create an application to install on our mobile which extracts this identifier according to our wallpaper. To what end? In a very extreme case, imagine that we install Twitter with two active accounts, and with this identifier it would be possible to conclude that the two accounts are present on the same phone. Or that we install an app with one user, remove it and reinstall it with another. As long as we don’t change the desktop background, the ID would be the same.
This procedure created to extract the identifier of our wallpaper is still a curiosity, because for it to represent a real risk for our privacy, it would need, for example, to be able to be executed via a web. But it has to be an application installed on our phone that can access the API, and therefore everything becomes much more complex. However, it is curious to know that there are these procedures which can generate a unique identifier based on our personalization, and that it is “easy” to use our wallpaper thanks to the API of the system itself. . Our advice? If you are a fan of conspiracy theories, use generic wallpapers.
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