In brief: An artist from Berlin has proven just how easy it can be to manipulate Google Maps' real-time traffic data. With a wagon full of phones, he was able to create virtual traffic jams and presumably reroute traffic, causing others to unnecessarily avoid the area. Clever or dangerous?

Google for well over a decade has used colored overlays in its mapping application to illustrate real-time traffic conditions. Green means smooth sailing, yellow indicates some crowding and red signifies a bona fide traffic jam.

This information about your commute is deemed invaluable to many, but did you ever stop to question where Google and others source their data from? Look no further than the trusty ole spy in your pocket, otherwise known as your smartphone.

Mapping providers like Google rely on crowdsourcing to collect speed and location information from smartphone users. By analyzing the movement and congestion of phones, they’re able to determine traffic conditions with a reasonable level of accuracy. That is, until a prankster like Simon Weckert comes along.

Weckert gathered 99 smartphones, loaded each one with the Google Maps app then walked around town with them in a wagon. As Weckert appears to demonstrate in the clip above, the behavior succeeded in creating a virtual traffic jam, turning green streets red within the app.

Presumably, this also affected others by rerouting them to avoid the “traffic jam.”

For its part, Google seems to be taking it all in stride. A spokesperson for Google told 9to5Google that “Whether via car or cart or camel, we love seeing creative uses of Google Maps as it helps us make maps work better over time.”

Masthead credit: Google Maps by XanderSt