"We think of GPS maps as guides. They are the sometimes annoying, always calm, recorded voice in our car that steers us through unfamiliar places," reports Gregory Warner. "But maps are also public records that can help slum dwellers negotiate with city authorities."
"The slum-mapping movement [that has been brought to Mathare] started in India about a decade ago and more recently migrated to Africa," he explains. "The idea is to make slums a reality for people who would never set foot in one."
"A map can be entered as evidence in court to stop evictions. It can be reprinted by international advocacy groups to raise awareness. It can be presented to city planners, as a puzzle to be solved."