There are APIs for everything. The popular ones like Google’s mapping APIs, or Twitter’s REST apis. But you can use webhooks to close the integration loop.

Looking for example REST API and Mautic API documentation? This article gives a great high-level review of how to integrate Mautic API with third parties.

The Mautic Developer Hub provides a great set of resources and Mautic API for marketing automation developers working with Mautic and the Mautic SDK.