An AI-powered tool helped blind people make sense of the world - then ran into privacy concerns. Be My AI user, the BBC's Sean Dilley, in Washington DC, tells us what happened next. A rare interview with the boss of Spotfiy, Daniel Ek, who tells us there's a place for AI in music making. And reporter Marc Cieslak tells us about second thumbs and brain hacking, as he explores the mind boggling world of neural interface technology.

(PHOTO: A blind man using a mobile phone. Credit: Agrobacter. Copyright: Getty Images.)