"Alexa, I'm leaving."

"OK -- I'll be on guard."

That's the gist of Alexa Guard, a new feature from Amazon that lets your Echo devices keep an ear out for trouble when you're away from home. If Alexa hears something after you've put her into Guard mode -- a smoke alarm ringing or the sound of shattering glass, for instance -- she'll send you a notification. If you're an ADT or Ring subscriber, she'll notify your home security monitoring service, too.

Another feature: If you want, Alexa will cycle your smart lights on and off while you're away to make it look like you're home.

First announced back in September of 2018, Alexa Guard is now available with all Echo devices in the US. I was able to turn the feature on in my own home when it first began rolling out last December, and spent some time testing it out. Below are some takeaways.

Note: This article was originally published Dec. 17, 2018 and was updated, May 14, 2019 with Amazon saying that Alexa Guard is now available with all Echo devices in the US.

Enlarge Image Screenshots by Ry Crist/CNET

Yep, it works!

With far-field microphones in every Echo device, Alexa is already a pretty good listener. Alexa Guard puts those mics to use by listening for the sound of glass breaking or the sound of alarms when you aren't home.

Enlarge Image Screenshot by Ry Crist/CNET

And, my early impression is that it works pretty well! I didn't have a spare window to smash at my place, but I played a YouTube video of glass break sound effects near one of my Echo devices, and immediately received a notification on my phone that Alexa heard something that sounded like glass breaking. The same thing happened when I tested with the sound of a smoke alarm going off.

Note that some other security providers offer ways to listen for trouble, too. In some cases, the hardware might be more refined than what Alexa is offering. For instance, SimpliSafe offers an optional glass break sensor as part of its system's offerings. That sensor wouldn't fire off in my tests when I played sound effects -- I actually had to break a piece of glass in order to trigger it (SimpliSafe even says it can distinguish between the sound of a window getting smashed and the sound of someone dropping a dish).

Amazon's algorithm doesn't seem to be as advanced as that, but it's still an additional layer of protection while you're away. And when Alexa hears something, her notification offers the immediate option of using Drop In to listen through your Echo device. If you want, you can even broadcast yourself telling the potential intruder that you're calling the police as a means of scaring them off.

Enlarge Image Screenshot by Ry Crist/CNET

Alexa can't call 911

Still as Amazon notes as you're confirming setup in the Alexa app, "Alexa Guard is not a replacement for an alarm system or life safety devices. Amazon does not monitor Smart Alerts and cannot contact emergency services on your behalf."

That last bit is really important. Say you're out on vacation with Alexa Guard turned on. Your Echo device at home hears the sound of your smoke detector going off, and Alexa sends you a notification. Unfortunately, you're playing in the hotel pool with the kids, and you miss the notification. Alexa won't act on your behalf at this point the way a professional monitoring service would. It's on you to see the notification and act accordingly.

That said, if you subscribe to a professional home monitoring service through ADT, Alexa will forward those Smart Alerts to them. With Ring, Amazon says that users can request dispatch of emergency responders directly from the Ring app if they are subscribed to the Ring Protect Plus plan.

And if you're using an Alexa-compatible home security system that she can already arm and disarm with voice commands, you'll be able to set it so that happens automatically whenever you turn Guard mode on and off. And if you're disarming your system, she'll still ask you for a numerical PIN code before doing so. That's a touch that saves you from needing to give two separate voice commands as you come and go. Just say, "Alexa, I'm leaving" when you're walking out the door, then "Alexa, I'm home," followed by your PIN code when you return.

Away Lighting is smart and simple

Enlarge Image Screenshot by Ry Crist/CNET

Along with listening for trouble, Alexa Guard will let the assistant toggle your smart lights on and off while you're out to make it look like you're home -- and potentially deter any would-be burglars from attempting a break-in.

You can enable the feature with a single tap when you're turning Alexa Guard on in the Alexa app for Android and iOS devices. Once you do, the app will list all of your smart lights, and include them all in Away Lighting by default. If there are any you'd like left out, just uncheck them.

The feature asks for your zip code when you're setting it up -- Alexa uses that zip code to know what time sunset is in your area each night. Away Lighting will only run when it's dark out.

From there, you should be all set. When Alexa Guard is active and set to Away mode, your lights will automatically cycle on and off. The feature worked well when I tested it, and was even smart enough to automate some lights in tandem where it made sense -- "Bedroom Ceiling Light 1" and "Bedroom Ceiling Light 2," for instance. I didn't need to set that up; Alexa just figured it out.

I also appreciated that the Alexa app gives you a detailed rundown of Alexa's automated moves during Away Lighting. That's good for micromanagers (and, admittedly, for guinea pigs like me who want a closer look at what Alexa's up to).

The only hiccup I encountered: a smart plug that the Alexa app was reading as a light. It was a leftover from a recent review where I had it hooked up to a space heater, and since the Alexa app was reading it as a light and not a plug, Alexa included it in Away Lighting by default. That's obviously not good -- you don't want your space heater to automatically turn on and off while you're away from home.

I reported that issue to Amazon, and it has since been addressed: The plug in question will now register as a plug when you sync it up with Alexa. Ideally, the certification process for "Works with Alexa" gadgets should catch issues like these before the integrations even go live, especially now that Alexa wants to turn things on and off on our behalf.

Amazon tells me Guard will work with Echo Show, Echo Plus, Echo Spot, Echo Input, and the latest generation of Echo and Echo Dot devices.



“We will support additional Echo devices once the feature is generally available.” https://t.co/udTFytKLPS — Ry Crist (@rycrist) December 16, 2018

It works with every Echo now -- even older ones

I've got a couple of Echo devices in my home -- a first-gen Echo in the living room, a second-gen Echo Dot in my bedroom and a first-gen Echo Plus that I picked up on sale a while back to serve as a hub for cheap Zigbee smart bulbs. I keep that one in the bathroom for shower-time singalongs.

However, when I enabled Alexa Guard in December, my Echo and Echo Dot didn't come along for the ride. Only current-gen Echo and Echo Dot speakers worked back then, along with the Echo Show, Echo Plus, Echo Spot and the Echo Input. When I asked about this, Amazon said, "We will support additional Echo devices once the feature is generally available."

Well, the feature is generally available now, and Amazon kept its word -- the first-gen Echo and the first- and second-gen Echo Dots can go into Guard mode now, too.

"Echo Spot, Echo Input, and all generations of Echo, Echo Plus, Echo Dot, and Echo Show will now support Alexa Guard," an Amazon spokesperson confirms.

That's a great development for owners of earlier-gen Echo devices who didn't want to have to buy new speakers in order to try the feature out.

There's room for Guard to grow

It's clear that Amazon sees significant potential for Alexa in the DIY home security category. The company already owns the smart security camera brand Blink; in the beginning of 2018, it acquired the popular video doorbell startup Ring, too. Shortly thereafter, it started offering Alexa-centric home security packages that bundled DIY systems with an Echo Dot for voice arming and disarming. Just recently, the Alexa team added new software support for things like motion detectors and security keypads.

In short, there's an awful lot of movement here -- and a lot of competition, too. Aside from established players in the home security industry and the slew of DIY security startups we've seen in recent years, Google already offers app-enabled, DIY security via Nest Secure, and Apple offers plenty of security-minded automation via Apple HomeKit. Neither of those leverage the microphones that make Siri or the Google Assistant work, though. Amazon is out in front here, at least in that regard.

Along with bringing existing Echo hardware into the fold, I'd expect Amazon to make use of the yet-to-be-released Echo Auto, as well. That in-car Echo device will be able to track when you come and go -- automatically putting Alexa into Home mode whenever you park in the driveway seems like a natural fit. I'd also like to see Amazon do more to bring cameras into play. I use a couple of Blink cams in my place that I picked up on Black Friday -- right now, they don't factor into Alexa Guard at all.

At any rate, we'll keep an eye on the feature as Amazon continues developing it. By all early indications, it looks to be off to a good start.

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