Saqib Shaikh is a software engineer at Microsoft. He has also been blind since this age of seven, and has long dreamed of technology that could describe the world around him in real time. And now, he's made it. He explains how the Seeing AI voice assistant app describes the world around him.

----------What does a city have to do with obesity? New AI uses satellite imagery and Google Street View to show how urban design and obesity in US cities are related-without looking at a single person. Elaine Nsoesie, one of the researchers who designed the algorithm, explains how.----------Water is something that most of us take for granted. But the city of El Paso, Texas, is one of the most arid places on the planet-and water is a precious commodity. So Ed Archuleta designed a system to recycle most of the city's water-even sewage. And he says it's a protocol that many more cities are going to have to adopt as climate changes.

----------What started off as a school project became one of the world's most popular nature app - with a new observation recorded every 45 seconds. iNaturalist helps anyone identify plants and animals. Scott Loarie, the Co-Director of iNaturalist, discusses how iNaturalist combines the power of citizen science and big data.

----------Photographs can be more than just memories. The University of Victoria's Mountain Legacy Project holds the world's largest collection of current and historical mountain photos. And they return to those sites in the Canadian Rockies to retake those photos to track how the mountains are changing. Journalist Meg Wilcox joined the team as they photographed vistas that were first captured over a century ago.