HomePod, unveiled at Apple’s annual WWDC conference in San Jose, Calif. on Monday, will be able to play music on command from Apple’s streaming Apple Music service, using Siri to handle voice commands. It will also serve as a home automation assistant for turning on lights and providing information about traffic, weather, and stocks.

Amazon has a nearly two-year head start with its popular Echo home speaker, which has thousands of skills and features using its Alexa virtual assistant. Apple must therefore play catch up on features and capabilities.

HomePod, available starting in December 2017, is a 7-inch cylinder that’s nearly the size of a small potted plant. The exterior, which is made of mesh, comes in white and gray.

HomePod will also include an A8 chip, which is the same chip that powers processing for the iPhone.

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The major difference between it, Echo, and another rival, Google’s Home, is cost. Apple said the device will cost $349 and will be available in December in the U.S., U.K., and Australia. In comparison, Echo costs $180 and Google Home costs $129.

In its presentation, Apple emphasized playing music using HomePod, an attempt to differentiate it from its rivals. It also said that Siri has been updated to understand music-focused commands like “play something mellow” or “add that song to my workout playlist.”