Previously, users of these devices had to long press the home button to access Alexa.
According to Amazon, "millions of customers" have multiple Echo speakers in their homes. However, if you are using the Fire 7 or Fire HD 8 on battery power, the screen must be on to use Alexa hands-free. All you need to do is say something like, "Alexa, announce that dinner is ready", and the "Dinner is ready" part will be announced to your family members. The company is calling it Alexa Announcements, and the functionality is very similar to the broadcast feature Google Home has had since late a year ago.
Amazon did clarify that, as of right now, Alexa Announcements will only be rolling out to USA and Canadian customers.
Amazon said the new hands-free model will be available to Fire HD 7 and 8 users when their device is either plugged into a power source or the screen is lit up and in use. Just as with Amazon's other multi-Echo features, like Drop In, multi-room music, and calling & messaging, the goal is to encourage greater adoption of the smart speakers in a broader number of rooms.
If you have a multi-room set of Amazon Echo hardware, let us know in the comments if you can get this new feature working!