The feature does come with limitations, though. For one, you can only send messages to ten contacts, which you'll have to pre-program through the Alexa app for smartphones. You'll also have to have a compatible device and plan. If you're not sure if you have either, you'll have to download the voice assistant's app to try it out. That's assuming you already have an Amazon speaker -- in case you don't have one yet, you can also get the Echo or the Echo Dot directly from AT&T's new website for the Alexa skill.