What can technology do to tackle the question of sustainability?

David's just got back from IFA in Berlin, a meeting of more than 150,000 people to marvel at technology. But tech has a cost; this industry contributes around 2% to 3% of global greenhouse gas emissions. So what opportunities are their to learn, to change practices and to help consumers make better informed choices? We chat about Fairphone and their push towards repair rather than replace, and we talk to Uwe Schulte, a procurement expert turned sustainability consultant and guru. What lessons are their for us all?