In Nairobi, the technology for mobile payment is soaring ahead of the more physical asphalt infrastructure on the roads, says Mr Otieno.
Traffic congestion is a huge problem, he says, and regulatory costs and taxes are high.
Meanwhile the government’s megaprojects - with a projected cost of $50 billion (£34.9 billion) - offer new real stations, an upgraded airport, and ports like that under construction in coastal Lamu, but not much for the two largest city’s crowded roads.
But getting funding for ventures in mobile technology in East Africa’s Silicon Savannah, says Mr Otieno, is easier.
“Companies there are ready to fund ventures that revolve around mobile money technology,” he says.
“It only maybe needs to be given much more publicity,” he adds, “so young people who have ideas about business know how to access it.”
For his part, Mr Otieno looks forward to “getting it right in Kenya, then trying other countries”.
And Mr Eisen’s Maramoja also looks forward to scaling up, once he feels he’s perfected their operations – “otherwise we’re just scaling our problems,” he says.
Meanwhile Easy Taxi has benefited from the attentions of the German incubator Rocket Internet, and four funding rounds which have left it with it over $77 million to scale in the Middle East and Southeast Asia. It now has 185,000 drivers around the world.
Mobile money powered taxis, clearly, are going places.