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Back in May, Amazon added a phone-call feature to its line of Echo smart speakers. Just one catch: You could call only other Echo owners.

Last week, along with the announcement of new Echo devices, Amazon quietly eliminated that limitation. Effective immediately, you can use any Echo speaker to call landlines and mobile phones. For free.

Try it! Just say the following: "Alexa, call 800-435-7669." That's the number for the American Red Cross, just in case you felt like making a donation today, but Amazon allows for calls to "most" numbers in the US, Canada and Mexico. However, you can't use an Echo to call 911 or any other emergency services unless you have an Echo Connect. See below for more details on the Connect.

You can also tell Alexa to call anybody in your phone's address book -- provided you allowed access to it when you installed the Alexa app.

Either way, Alexa will ask you to verify the number or contact you want to call. It's a somewhat annoying second step, but understandable given that there's no screen to verify the number being dialed (unless you're using an Echo Show ( )).

Whoever you call will see your mobile phone number as the caller ID.

If you like the idea of using your Echo as a speakerphone, you might want to add an Echo Connect to the mix. This $35 box taps into your existing home-phone service, meaning that number becomes the Echo's caller ID. It also allows you to receive calls as well as place them and adds 911 support to the mix. The Connect is due to ship mid-December.

What do you think of the Echo's new calling capability? Now that there's landline and mobile support, is it a feature you'll use?

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