You can now use Alexa to make free phone/video calls and send messages with some Android, iPad and Amazon Fire tablets. Previously, both parties needed an Amazon Echo speaker to be able to message or chat with each other.
This new feature is activated differently depending which device you have. The Amazon Fire HD 10 tablet just requires you to ask Alexa to make a call. Other Fire tablets, which don't have Hands-Free mode, need you to tap the home button to use the feature. All other tablet users will need to open the Alexa app to make a call or send a message.
Nothing has changed about receiving calls with the Alexa app -- you don't need a tablet or speaker. Using Amazon's Drop In feature, your tablet will act as a two-way radio with any other tablet or Echo device that you authorize.