A German performance artist has been tricking Google Maps into thinking the streets of Berlin are congested with traffic by lugging around a cart full of smartphones.

On Saturday, Simon Weckert posted video of his hack, which shows him pulling a cart carrying 99 smartphones around the German city. As he does, Google Maps begins to react; the color of each street Weckert moves through turns from green to red, an indicator that traffic is bad and that users should avoid the area.

"Through this activity, it is possible to turn a green street red, which has an impact in the physical world by navigating cars on another route to avoid being stuck in traffic," Weckert wrote on his website.

The hack exploits how Google Maps relies on tracking smartphones in real time to determine traffic patterns. A large group of phones together normally indicates a street is congested with cars, which signals to Google Maps a traffic jam is likely taking place.

According to Wired, Weckert realized he could toy with the function almost three years ago when he entered an empty street in Berlin that Google Maps mistakenly thought was packed with cars. In reality, the area was simply occupied by a mass of people, who were all carrying smartphones.

To pull off the hack, Weckert borrowed 99 phones from friends and rental companies. With his cart, he then began walking the devices up and down a specific city street. Although Google Maps wasn't tricked instantly, it started to react within the hour, changing the street color from green to red. Drivers dependent on Google Maps would've also been told to needlessly travel in a different direction when the street was in fact open.

Weckert's goal with the hack is to show the public how technology is increasingly shaping our lives. "I have the feeling right now that technology is not adapting to us, it's the other way around," he told Wired.

In response, Google told 9to5Google: "We've launched the ability to distinguish between cars and motorcycles in several countries including India, Indonesia, and Egypt, though we haven't quite cracked traveling by wagon. We appreciate seeing creative uses of Google Maps like this as it helps us make maps work better over time."

Users can control and turn off the location tracking by going to the settings function in their Google accounts.