---
title: "Introduction"
url: https://docs.catalyst.zoho.com/en/tutorials/leadmanager-appsail/springboot/introduction/
description: "Build a Lead Manager application and host it on AppSail. The app connects to your Zoho CRM account using Catalyst connectors, and enables you to view, create, update, or delete leads from the Leads module in your CRM."
last_updated: 2026-08-17T12:16:04Z
service: All Services
type: tutorial
related_links:
  - name: "Project Directory Structure"
    url: /en/cli/v1/project-directory-structure/introduction/
  - name: "Catalyst SDK for AppSail"
    url: /en/serverless/help/appsail/key-concepts/catalyst-configurations/#implementing-catalyst-sdk-in-appsail/
---

# Lead Manager App Using AppSail

### Introduction

This tutorial will help you build a  **Java Spring Boot** application web application called **Lead Manager**. This web app will allow you to connect with your [Zoho CRM account](https://www.zoho.com/in/crm/) and enable you to manage leads in your organization. You will be able to access, add, edit, or delete leads in the [Leads module](https://help.zoho.com/portal/en/kb/crm/sales-force-automation/leads) in your CRM account directly from this application.

The connection to Zoho CRM is established using [OAuth 2.0 authentication protocol](https://docs.catalyst.zoho.com/en/api/oauth2/overview-and-terminology/#OverviewandTerminology). We will generate an `OAuth Access Token` for the *Lead Manager* application and use it to authorize the connection to access CRM data. The authentication requirement in this tutorial is handled using [Embedded Authentication](https://docs.catalyst.zoho.com/en/cloud-scale/help/authentication/native-catalyst-authentication/embedded-authentication/introduction/).

We will also implement a [Catalyst Connector](https://docs.catalyst.zoho.com/en/sdk/java/v1/connectors/connectors/) to manage this access to the CRM account. The connector will refresh the `Access Token` automatically each time it expires using a `Refresh Token`, and will maintain a constant connection between the client and the CRM account.

These tokens can be generated after registering the client application in the [Zoho API console](https://api-console.zoho.com/) and obtaining the required credentials.

The client application will look like this:

![catalyst_tutorials_leadmanager_appsail_first_look](https://catalyst-docs-development.zohostratus.in/images/tutorials/leadmanager-appsail/catalyst_tutorials_leadmanager_appsail_first_look.webp)

The Lead Manager application employs components from the following Catalyst services:

- [**Catalyst Serverless**](https://docs.catalyst.zoho.com/en/serverless/):
  - [AppSail](https://docs.catalyst.zoho.com/en/serverless/help/appsail/introduction/): To host the independent *Java Spring Boot* application. We will be building the front-end of the app as well as the back-end logic, and bundling them together to deploy them on AppSail.
- [**Catalyst CloudScale**](https://docs.catalyst.zoho.com/en/cloud-scale/):
  - [Data Store](https://docs.catalyst.zoho.com/en/cloud-scale/help/data-store/introduction/): To store the `Refresh Token` and [UserID of the Catalyst user](https://docs.catalyst.zoho.com/en/cloud-scale/help/authentication/user-management/users/introduction/) fetched by the function resource. The `Refresh Token` is fetched from this table by the function, whenever a new `Access Token` needs to be generated.
  - [ZCQL](https://docs.catalyst.zoho.com/en/cloud-scale/help/zcql/introduction/): To fetch data from the *Data Store* through querying.
  - [Catalyst Authentication](https://docs.catalyst.zoho.com/en/cloud-scale/help/authentication/introduction/): To implement a [Zoho social login](https://docs.catalyst.zoho.com/en/cloud-scale/help/authentication/social-logins/configuring-social-logins/#enable-zoho-social-login) in the client application’s login page, in addition to the standard login option, we will be implementing the [Embedded Authentication type](https://docs.catalyst.zoho.com/en/cloud-scale/help/authentication/native-catalyst-authentication/embedded-authentication/introduction/) in this tutorial.

We will use the [Catalyst web console](https://console.catalyst.zoho.com) and the [Catalyst Command Line Interface](https://docs.catalyst.zoho.com/en/cli/v1/cli-command-reference/) (CLI) to build this application.

> **Info:** You will be given the code for the files to be included in the function and client components in this tutorial. You will just need to copy the provided code and paste it into the appropriate files as directed.

### Application Architecture

The Lead Manager application’s architecture is depicted below:

![catalyst_tutorials_leadmnager_appsail_architecture_dig](https://catalyst-docs-development.zohostratus.in/images/tutorials/leadmanager-appsail/catalyst_tutorials_leadmnager_appsail_architecture_dig.webp)

The entire workflow of the application will be explained in more detail when you [code your front end logic](https://docs.catalyst.zoho.com/en/tutorials/leadmanager-appsail/springboot/code-app), which we recommend you check out as you follow along the steps.