Although it’s home to some 70,000 people, there are relatively few official street names and addresses in Rocinha, Rio, the largest Favela in Brazil – a real problem for its inhabitants.

UK tech start-up What3Words has the answer: an app that fits inside a smartphone and is much more precise than a GPS. The idea is to give every single spot on the globe a unique and easy address to remember – words that translate to a specific set of coordinates.

3 word addresses = #delivery in Favelas. Vote to change the world http://t.co/D5MxlIssIC #voom #startup #tech #change pic.twitter.com/AUDnHRva1r— what3words (@what3words) 3 Juin 2015


“With GPS coordinates it’s actually pretty common to mix up two of the numbers and the worst thing that could happen is maybe you’ve ordered pizza or something and the guy actually goes to the wrong place in your town, so you were close enough that you didn’t know that you were wrong,” explains What3Words CEO Chris Sheldrick. “So our office is here at In