Gregory Warner

You're out navigating the jammed sidewalks of Kenya's capital city when you suddenly realize you're in desperate need of a toilet. You crane your neck over the crowds, vainly seeking a McDonalds, a Starbucks — no such luck. What next?

There could be an app for that. Twendeloo, which is Swahili for "Let's Go to the Loo," would allow you to use your phone to locate the nearest public restroom in Nairobi's business district, then give it a rating for cleanliness.

When Duan Biggs was growing up in the Kruger National Park in South Africa, he used to watch elephants and rhinos walking past his bedroom window. He left home to pursue degrees in biology and economics, and when he returned in 2011 the park looked and sounded "like a pseudo war zone," he says.

"There'd be helicopters flying overhead all the time," he says. "I remember one afternoon coming back to my home from a game drive and the bush was crawling with people with assault rifles, from the army, from the police, and from National Parks. They were looking for poachers."

It says a lot about the state of the war against poachers in Africa that the Lewa Conservancy, a private sanctuary in Kenya with 12 percent of the country's rhinos, recently appointed a CEO who has never studied zoology or biology. Instead, Mike Watson is an ex-captain in the British army.

His training has already come in handy. Take, for instance, a visit to a crime scene earlier this year: a rhino carcass splayed out in the mud.

Imagine you're flying in a two-seater plane over Africa, and, in an effort to see how elephants are faring, your job is to count all the ones you see. Over the savannah, that's easy. But how do you peer into the forests, where all you see is treetops?

For years, the zoologists who tried to do this just guessed. But in the late 1980s, conservationist Richard Barnes devised a method to take an elephant census in the densest of forests.