Enlarge Image Tyler Lizenby/CNET

Alexa's taking a small step into the smart home, with a new update that brings Belkin WeMo and Philips Hue devices under Amazon Echo's control.

The update comes after months of speculation that Amazon Echo, a smart, voice-controlled speaker, could potentially play a role in the emerging connected home. Using built-in microphones, Echo responds to voice commands by way of "Alexa," Amazon's Siri-like take on the virtual assistant. With Bluetooth and Wi-Fi radios packed under the hood, there didn't seem to be much stopping Alexa from taking control of lights, switches, and other smart-home gadgets just as easily as she plays songs from the Amazon Prime Music library. Some intrepid hackers have already retooled Echo to do exactly that.

The update makes it official, though for now, Echo support is limited to Belkin WeMo switches and LED light bulbs, along with connected lights from Philips Hue. Moving forward, it's easy to imagine things like locks, thermostats, and sensors coming into play, as well -- although none of those controls seem to be built in to the Echo API just yet. When I tried telling Alexa to lock the door, she told me she'd add "lock the door" to my to-do list.

Getting everything working was a pretty easy process when I tested it out. After downloading the most recent version of the Echo app, simply ask Alexa to discover new devices. Echo then runs a quick scan, detecting any devices you've got installed on the same Wi-Fi network.

For Philips Hue lights, you'll need to press the button on the center of the Hue Bridge during the discovery process, but with WeMo gadgets, no extra action is required. All in all, the process took me less than a minute, and from there, I was able to tell Alexa to turn everything on and off without incident.

Certain limitations apply. For starters, you'll need to refer to each device by the specific name you've entered into its respective app. You also can't use Alexa to schedule automated changes -- if you want to schedule your lamp to turn on at 6 p.m., or in 30 minutes, you'll still need to pull out your phone and fiddle with an app.

Enlarge Image Colin West McDonald/CNET

Additionally, Echo can't currently change the color of your Philips Hue lights. Alexa can turn them on and off, and she can also dim them up or down, or to a specific percentage, but she can't turn them purple, or activate any preset scenes from the Philips Hue app.

However, you can combine devices into "groups" in the Echo app, then control them all at once. I made a group called "Lights" that included a Philips Hue bulb and a desk lamp plugged into a WeMo Switch. Telling Alexa to "turn the lights on" switched them both on simultaneously.

Enlarge Image Tyler Lizenby/CNET

In some ways, voice control seems like the next frontier for the smart home. It's one of the major selling points for Apple HomeKit, with the first wave of Siri-compatible smart devices expected to start hitting retail shelves within weeks. Google's in the game, too, with voice controls for the Nest Learning Thermostat, while Microsoft lets Windows users control Insteon's smart home gadgetry using Cortana.

A big part of Amazon Echo's appeal is that it's always on, and always listening. Just say "Alexa" (or "Amazon," your other wake word option), and Echo lights up, ready to follow your command. With enough devices under Alexa's control, Echo's approach could position it to serve particularly well as the ear of the connected home, a simple and undeniably cool way of activating your gadgets without needing to pull your phone out of your pocket.