You can send texts via Alexa but only on Android phones

Daily Mail 

So much for needing your phone to send text messages. Thanks to a new software update, you can now use Alexa to deliver SMS text messages to any phone. There are some caveats, however. It only works for Alexa users in the US with an Android device that also have the Alexa app installed on their phone. You also can't use the feature to text 911 or participate in group text messages.