While the idea of retail giants like Amazon dropping parcels from the sky via drone may be a long way off, in East Africa momentum is building over the idea of drone delivery in hard to reach places. In the island of Juma near Mwanza, one of hundreds of remote inhabited islands in the vast expanse of Lake Victoria, an ambitious new drone project called the Lake Victoria Challenge is taking place. Technology reporter Jane Wakefield visits Juma to see first-hand how the concept could work.