Governments around the world are planning to roll out contact tracing apps to help contain the spread of coronavirus. But will they work? Ed Butler speaks to BBC technology reporter Chris Fox about the technology that underpins them, and to researcher Natalie Pang from the National University of Singapore about the experience of Singapore's TraceTogether app, launched last month. But conventional human contact tracing has been around for decades. UK contact tracer Karen Buckley describes the challenges of the job, and John Welch from the non-profit Partners in Health describes his experience of contact tracing amid the Ebola outbreak in Africa and argues that apps are no substitute for an army of dedicated human contact tracers.

(Photo: A man holds a smartphone showing a contact tracing app launched in Norway this month. Credit: Getty Images)