When President Obama was a guest on Marc Maron’s WTF podcast in 2015, the episode was downloaded a record 900,000 times in 36 hours. Now, Hillary Clinton is looking to get in on the action by launching her own podcast called With Her, which she'll co-host with journalist Max Linsky.

In an effort to engage with core customers, online fashion retailer ASOS is set to launch a weekly podcast focusing on female business owners. Having already rolled out a monthly print magazine, the brand hopes its newest venture can reach an even wider range of its Gen Y and Z audience.

In late 2015, The Message knocked podcast royalty This American Life off the top of the iTunes charts. The eight-part series – from GE – attracted over a million listeners, becoming the most successful branded podcast to date. But why were people tuning into what’s essentially a long-form ad?

Averaging 2.2 million listeners per episode, NPR’s Serialpodcast is not just a cultural phenomenon, but a game-changer for a formally underappreciated medium. But why has the story of a 1999 murder in Baltimore struck such a chord? And what is it about the lure of audio that’s driving a talk radio revival?