A prototype of Apple's new HomePod is displayed during the 2017 Apple Worldwide Developer Conference (WWDC) at the San Jose Convention Center on June 5, 2017 in San Jose, California.

Apple's smart speaker is struggling to grab market share from the Amazon Echo and Google Home. A new analysis by Consumer Intelligence Research Partners found Apple's HomePod makes up only 6 percent of the 66 million units in the United States.

Although the number of smart speakers has grown, Apple's has failed to keep up with the rest of the market. The Google Home makes up 24 percent of the U.S. installed base and Amazon's Alexa-enabled Echo accounts for 70 percent, according to the report.

Apple's HomePod, at $349, is more expensive and more limited than other smart speaker. By comparison, Google offers smart speakers starting at $29.99 and Amazon's start at $19.99. While the HomePod prides itself on high-quality audio and the fact that it does not store conversations in the cloud as other devices do, the number of services it supports is narrower compared with its competitors. Siri will only listen to commands to play music from Apple's own streaming service, and playing from other services, like Spotify, require a more complicated setup.

Apple has shifted its strategy around Apple Music. It is now starting to offer the service to smart speakers with bigger market share. In November, Amazon said Apple Music would be available on the Echo, marking a rare collaboration between the two companies. The move comes as Apple looks outside its own closed-off ecosystem to drive more subscribers for its services.

Mike Levin, co-founder and partner in Consumer Intelligence Research Partners, said Amazon and Google's strategies of offering lower-priced devices so people can own more than one in their home seems to be working. The report said 35 percent of owners have more than one device as of the December 2018 quarter, compared with 18 percent the previous year.

"Their strategies appear to include persuading owners to use smart speakers in multiple rooms, which helps create more active usage of the voice platform," Levin said. "And, Google has mostly caught up to Amazon in this strategy. A year ago, almost twice the percentage of Amazon Echo users had multiple units as Google Home users. Now, about one-third of both Amazon Echo and Google Home users have multiple units."

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