Amazon has just announced the Echo Show, the latest addition to the Echo range of smart home devices. With the launch of the Echo Show, Amazon has announced a new calling and messaging feature coming soon, that will let you make and receive calls, as well as send messages between Echo devices and the Amazon Alexa app for iOS and Android.

But what exactly is the new feature all about and how do you go about using it? Let us explain.

Amazon Alexa calling and messaging is a new way to contact family and friends that also have Echo devices in their home, or the Alexa app installed on the iOS or Android device.

It works with all current Echo devices - although only in the US for now - so if you have an Echo Dot or Echo, you can still call or message an Echo Show and vice versa. You can also call from Echo to Echo, Echo Dot to Echo Dot and so on.

The best bit about the new feature is that it's completely free to use as it works over Wi-Fi and mobile data, so you don't need to invest in a talk plan.

If you're using calling and messaging through an Echo device, you'll need to make sure you have the latest software update installed. You'll also have to enable Alexa calling and messaging in the system's settings, and anyone you'll want to call with have to enable this function too.

You'll be able to see all your contacts that have the function enabled from within the Alexa app.

Once you do, it's simply a case of using your voice to place a call to someone with an Echo device or the Alexa app on their phone or tablet.

If you and and the recipient have an Echo Show, you'll be able to make video calls, in a similar way to FaceTime on Apple devices and Skype.

To start a call, you'll need to wake the Echo up by saying "Alexa" and then ask it to call someone, for example "call dad". If someone tries calling you, your Echo device will display a green ring and give out an audio alert.

You can tell Alexa to answer the call, or ignore the call, but going by the promotional video Amazon has produced, Echo isn't able to tell you who's calling, so you could end up ignoring your mum's call!

It's a similar process to send messages, and if you've sent text messages from your phone using Siri, Google Assistant or Cortana, there isn't anything new to learn. Simply say "Alexa, message [whoever you want to message]", then dictate your message and Alexa will send it.

As with calls, you'll hear a chime when you receive a message from someone else, and the green ring will light up. You can then ask Alexa to play your messages.

Drop In is a separate feature that can be used with Echo Show. Amazon says in most case you'll use video calling, but Drop In is there so you can easily check in with an elderly relative, let the family know dinner is ready, or check a camera in the nursery. It sounds like you won't need to call someone else, but can simply access the camera on another Echo Show.

You can pick and choose which Echo Show devices Drop In is available on, and you can choose which contacts can have the privileges to Drop In on it. If you want, you can opt to not allow anyone to.

Amazon hasn't said when the feature will launch, but we'd expect it will be available alongside the launch of the Echo Show, which is 28 June.

Preorder the Amazon Echo Show from Amazon US