Message callback refers to the ability to set up a webhook or http callback to notify your server of a message event (message received, message delivered, message delayed).
How Bandwidth is involved with message callback
Bandwidth’s APIs can be configured to send message callbacks to a message callback URL.
What are the benefits of Bandwidth’s message callback
Combining both a voice and messaging callback (webhook) together is one of the first steps to integrating texting and calling to your application.