## Overview

[![calling-extensions-sdk on npm](https://img.shields.io/npm/v/@hubspot/calling-extensions-sdk.svg?style=flat-square)](http://npmjs.com/@hubspot/calling-extensions-sdk)

The Calling Extensions SDK allows apps to provide a custom calling option to HubSpot users directly from a record in the CRM.

A calling extension consists of three main components:

- The Calling Extensions SDK, a JavaScript SDK that enables communication between your app and HubSpot.
- The calling settings endpoints, which are used to set the calling settings for your app. Each HubSpot account that connects to your app will use these settings.
- The calling iframe, which is where your app appears to HubSpot users and is configured using the calling settings endpoints.

## Getting Started

1. Create an app from your [app developer account](https://developers.hubspot.com/docs/getting-started/account-types#developer-accounts), and create a [developer test account](https://developers.hubspot.com/beta-docs/getting-started/account-types#developer-test-accounts) to test your app.
1. [Install the Calling Extensions SDK](https://developers.hubspot.com/docs/api-reference/crm-calling-extensions-v3/calling-sdk#install-the-calling-extensions-sdk-on-your-calling-app) on your calling app. Alternatively, you can [run the demos](https://developers.hubspot.com/docs/api-reference/crm-calling-extensions-v3/calling-sdk#run-the-demo-calling-app) if you'd like to see the SDK in action first.
1. Learn how to [use the Calling Extensions SDK](https://developers.hubspot.com/docs/api-reference/crm-calling-extensions-v3/calling-sdk#using-the-calling-extensions-sdk).
1. View the [available calling events](https://developers.hubspot.com/docs/api-reference/crm-calling-extensions-v3/calling-sdk#events).
1. [Test your app](https://developers.hubspot.com/docs/api-reference/crm-calling-extensions-v3/calling-sdk#test-your-app).
1. [Get your app ready for production](https://developers.hubspot.com/docs/api-reference/crm-calling-extensions-v3/calling-sdk#get-your-app-ready-for-production).
1. [Publish your app to the HubSpot marketplace](https://developers.hubspot.com/docs/api-reference/crm-calling-extensions-v3/calling-sdk#publish-your-calling-app-to-the-hubspot-marketplace).

## Getting Help

1. [Review the FAQs](https://developers.hubspot.com/docs/api-reference/crm-calling-extensions-v3/calling-sdk#calling-sdk-%7C-frequently-asked-questions).
1. Learn how to [get help with HubSpot](https://knowledge.hubspot.com/help-and-resources/get-help-with-hubspot?_gl=1*7nomik*_gcl_au*OTQ3MjgyMDk4LjE3MzA4MzkyOTE.*_ga*MjA4MzEyMjM0Mi4xNzMwODM5Mjkx*_ga_LXTM6CQ0XK*MTczMTQyOTg1Mi40LjEuMTczMTQzMDQ1My42MC4wLjA.&_ga=2.181003488.658339848.1731429852-2083122342.1730839291).