What role can businesses play in filling Africa's cartographical gaps? And can better maps help fight diseases like cholera?

In her third and final programme about the progress being made in properly charting the continent, Katie Prescott asks what companies can do in locations where satellite images cannot penetrate dense rainforest and cloud cover, or in slums whose streets are not navigable by Google streetview cars.

She speaks to John Kedar of Ordnance Survey, Zanzibar planning minister Muhammad Juma, Tom Tom vice president Arnout Desmet.

(Picture: Satellite images of rural Tanzania; Credit: Google maps)