A crash course in changing the world.
"Innovate on existing platforms (We’ve got bicycles and mobile phones in Africa, plus lots of metal to weld. Innovate using that stuff, rather than bringing in completely new tech.)" This make so much more sense to me, simply solutions with small costs, will bring help to many. Again and again, this is stiffled by the need of so many, to make money out of these kind of things rather than doing it for the sake of helping people in great need.
One Such Idea is this Bicycle, I am not aware of the price but it must be a option for families in the Third world as shown below.