Google is unveiling a home-audio service so people can stream music in their homes using smartphones, broadening the company's effort to become a hub for digital entertainment.

The new service, called Google Cast for audio, works when people tap a button on their smartphone and choose a home speaker that has the same embedded technology to stream music through, according to Rishi Chandra, director of product management.

The service, which is being announced today at the Consumer Electronics Show in Las Vegas, was built atop the same technology as Chromecast, a small device that plugs into televisions and lets people access digital video services such as YouTube or Netflix.

“There’s actually a fairly big opportunity in the audio space,” Mr Chandra said. “You have this content on your phone – you listen to it all the time – but you want to easily extend that to better speakers in your house.”

Google is investing in new tools that provide online songs, movies and television shows as users increasingly access various screens for consuming media, a competitive area that has also attracted rivals including Apple and Amazon. com.

Chromecast, unveiled in 2013, has emerged as the number two media-streaming device, with 20 per cent of sales to US homes with broadband access during the first three quarters of 2014, according to Parks Associates.

– Bloomberg