Swedish music streaming service Spotify is offering an audiobook for the first time.

The free-to-use service plays tracks that are peppered with adverts just like commercial radio. However, for a £9.99 monthly subscription, users can enjoy ad-free listening.

Along with music, Spotify users can also enjoy Wired editor Chris Anderson's new book 'Free: The Future of a Radical Price', which is narrated by Anderson himself.

Spotify says: "Free considers a brave new world where the old economic certainties are being challenged by a growing flood of free goods - newspapers, DVDs, T-shirts, phones, even holiday flights."

"This is the first audiobook we've ever included in our catalogue. We're going to trial it, see what people think and who knows, maybe this is the start of something new for us," said Andres Sehr from Spotify.

UK users can get their hands on 'Free: The Future of a Radical Price' now, as Spotify.

Introducing audiobooks, is one of a number of changes Spotify is making to its service. The music-streaming service announced last month that it was improving sound quality of tracks for users that pay a monthly subscription.

'Premium' users are being offered an 'enable high bitrate' option in the preferences, which the company says doubles the current streaming quality and offers a sound-quality similar to CDs.