It's also been used by Iraqis and Taiwanese students during their anti-Beijing Sunflower Movement.
Last month, the concept kicked off in London, so I decided to road-test the model in the Spanish capital. His "Unforgettable Gastronomic Experience" proved just that, taking me to five belt-busting tapas bars over two-and-a-half hours.
The application has a simple rule: users get to download files as long as they share their own.
Its first noticeable function is the Search tool, which can be used to find images, audio, video, software, document, or other types of files.
To the uninitiated, this whole experience might be intimidating, but luckily, I have Jacobo, a Madrid native and an aspiring tour guide.
Jacobo is one of a clutch of locals who have signed up to a website called Trip4Real since it launched in 2013.