Amazon Echo. Image source: Amazon.com.

When Amazon.com (NASDAQ:AMZN) first introduced the Echo to a select group of Prime members by invitation only, it was an amusing gadget -- a wireless speaker that did a few extra things through voice commands.

It was a novelty with a hint of potential, but mostly it was an interesting-looking music player that could give you the weather, tell you a lame joke, and -- sort of -- help you shop on Amazon.com. Echo has Amazon's Alexa voice-recognition technology built in, but at first it didn't use it particularly well.

Think of Alexa as Amazon's answer to Apple's Siri or Microsoft's Cortana. It's a voice assistant that like Siri has more promise than practical use (Cortana is actually pretty useful). On Echo, however -- at least at first -- Alexa was an assistant that couldn't assist with very much.

But as Amazon made Echo more widely available, and then offered it to anyone willing to pay for it, the company started to add new features. Most were still a little gimmicky, but others liked that the device was able to deliver sports scores, news, traffic reports, and more, making it more helpful.

In recent weeks the company has added a voice-controlled calendar, which, along with its ability to set voice-controlled alarms and build to-do lists, has made Echo more useful as a device.

The most important change Amazon made, however, is turning Echo into a home management device. It's a bold play that positions Echo as a rival to Siri and Cortana (along with many others) when it comes to the the battle to control the home.

What is Amazon doing?
The Echo is now compatible with select Belkin WeMo, Philips Hue, SmartThings, Insteon, and Wink connected devices to control lights and switches in your home by voice. Amazon explained this broadly on its website:

"Use Echo to switch on the lamp before getting out of bed, turn on the fan or space heater while reading in your favorite chair, or dim the lights from the couch to watch a movie -- all without lifting a finger ... or even raising your voice."

The retailer makes it easy to buy Echo-friendly devices on its website, and it's bringing those efforts to in-store retail. That will put the unique device where people can see it, in stores next to home automation items it can control.

What will the Echo retail rollout be like?
Amazon is bringing Echo to more than 3,000 stores around the country in time for the holiday shopping season. It will be offered in select Home Depot, Staples, Sears, Brookstone, RadioShack, Fred Meyer, and P.C. Richard & Son stores, as well as several other retailers. (Here's the full list.)

"Our customers continue to show interest in smart-home products across the many categories we carry," said Home Depot Merchandising VP Jeff Epstein in a press release. "Amazon Echo is a smart device that helps make the connected home easy and fun."

Since Echo will benefit from having people play with it, that might make it a big seller for Brookstone, a store that specializes in higher-priced items that people like to experiment with in its stores.

"Our goal is to give customers the opportunity to see and try out the best in new technology and gifts, and Echo is a great fit for them," Brookstone CEO Tom Via said.

Amazon might have a winner here
Echo, which retails at $179.99, would be pricey just as a voice-addressable wireless music player with an improving assistant in Alexa. But it's a decent value because it can also stream music from many of the popular services, including Amazon's own Prime Music. Simply saying "Alexa, play The Replacements" brings up music from that group. Asking it to then "play 'Buffalo Tom Radio'" launches my Pandora station of that title.

That alone might not get people to shell out $179.99, but Echo is still appealing as a home automation hub. It's easy to use, and in-store displays could make Amazon's version of automating people's houses seem very accessible.

It's possible this could give the retailer an edge over the other companies racing to get a foothold in your living room. Amazon is sort of back-dooring its way into what could become a massive growth category, but it's doing so very smartly, and it might create a whole new area of revenue for the company, well beyond just selling the device.

Daniel Kline and The Motley Fool own shares of Microsoft and Apple, and the latter company is a Motley Fool recommendation. The Motley Fool owns shares of and recommends Amazon.com and Pandora Media. The Motley Fool recommends Home Depot. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.