Kaizen #116 - Client Types in Zoho API Console

Kaizen #116 - Client Types in Zoho API Console

Hello everyone!
Welcome back to another post in the Kaizen series!

This week, we will discuss different client types available in Zoho API Console, and when to use each.

When you register an app in Zoho API Console, you typically choose a client type based on how your application interacts with Zoho services.
Let us discuss the available client types and how authorization is handled for each.

Available client types

  1. Server-based
  2. Client-based
  3. Self client
  4. Non-browser-based
  5. Mobile-based

1. Server-based

If you have a web-based application that runs on a dedicated HTTP server and interacts with Zoho services by calling Zoho APIs via that server, you must register your app with this client type.
This client type is for applications that redirect the users to another URL on a web browser to authorize themselves, where they give consent to your application to use their data.
In other words, you must use this client type when you have a front-end web UI and require user intervention before your app can access user data via the dedicated server.

Consider that you are developing a web-based custom application. Users authorize that app via browser to allow their Zoho CRM data to be accessed and used by that application.
During the registration process in Zoho API Console, you would choose the "Web-based" client type.
OAuth 2.0 would be used for user authentication, allowing your app to securely access and interact with Zoho CRM data on behalf of the users.

Here is a gist of what happens:
  1. Users visit your website where you have the Login with Zoho button.
  2. When a user clicks it, that user will be redirected to accounts.zoho.com with the details of your app such as client ID, scope, redirect uri, access type as the URL parameters.
  3. Your app must make an API call to Zoho Accounts with the client ID, scope, redirect uri, and access type. Users are shown the data that your application wants to use.
  4. When users give their consent, Zoho redirects them back to your app.This will be the "Redirect URL" you give while registering your app.
  5. The redirect URL will have the authorization code(grant token) as one of the parameters, along with the location(user's domain).
  6. Your app must then make API calls from your web server to Zoho Accounts to generate access and refresh tokens with the generated grant token.
  7. You must store these tokens in your DB to access that user's data in Zoho CRM. While making API calls, you must send this access token in the header.
  8. Your app must also have the logic to regenerate access tokens from refresh tokens when the access token expires.
Note that your app must take care of storing user's details like email, organization ID, and tokens.

The following image shows the protocol flow.


You can use any of our server-side SDKs to simplify this process.
When you use our SDK, all you have to do is, generate the grant token and initialize the SDK with the client details and this token. The SDK takes care of access token generation, refreshing it, and token storage.


For more details, you can refer to the Accounts guide and CRM help doc.

2. Client-based applications

This client type is for applications that do not have a server and run exclusively on a web browser.
This is also called the Implicit flow as your app makes API calls to Zoho only when users are using your app.
This type of application loads data dynamically on the webpage, and accesses Zoho CRM data by making API calls via Javascript.

Consider the same example where there is a Login with Zoho button on your webpage.
Here is a gist of what happens when a user clicks it.
  1. Your app redirects the user to Zoho Accounts.
  2. Your app makes the authorization request with the client ID, redirect uri, scope, and response type as token.
  3. The user is shown the data that your webpage would use.
  4. When the user gives consent, Zoho Accounts sends the access token to the redirect uri as a parameter, along with the expiry time and the location of user's data in Zoho's accounts server.
  5. You can include the "email" in your scope parameter in the access token request to get user's information. The response will have a parameter called id_token that will be in the header.payload.signature format. You need to decrypt the payload section of the parameter using the base-64 decryption algorithm to get user information.
  6. Your app must then make API calls to Zoho with this access token to fetch data.
  7. When the access token expires, your app must take care of regeneration and storage.


As the API calls are made from your domain to a different domain(zohoapis.com), for security reasons, the browser will throw the CORS error. So, your domain will be registered while registering your app, and Zoho will know to allow the API calls made from that domain.

As the tokens are available on the browser itself, we recommend handling them with care.
When you use our client-side JS SDK, it automatically generates a new access token upon expiry.

3. Self Client Applications

When your application does not have a redirect URL or a UI, but performs only a backend job, and does not need user intervention, then you must choose this client type.

A self client is often used when the application and Zoho services are operated by the same entity, and you want to enable secure communication between them. For example, you have an internal reporting tool and integrate it with Zoho Analytics. In this case, both the tool and Zoho Analytics are operated by the same entity.
Similarly, consider that you have a legacy product management system and want to perform data sync between Zoho CRM and the system, then you must use the self client.

Here is a gist of what happens.
  1. You register your app as self client in Zoho API Console.
  2. You will get the client details such as ID and secret.
  3. You provide the scopes required for your app to access CRM data.
  4. You will receive the grant token.
  5. Your app must then make API calls to Zoho Accounts to generate access and refresh tokens.
  6. Your app can then use this access token to make API calls to Zoho CRM and use data.
You can refer to our older Kaizen post on this topic for more details.
Note that self client apps can also use any of our server-side SDKs. As already said, the SDK takes care of access and refresh token generation, refreshing the access token, and token storage.

4. Non-browser applications

This client type is for devices that do not have a user agent such a web browser. A TV, for instance.
Let us consider an example involving a smart TV application that integrates with Zoho ShowTime. In this scenario, the smart TV application acts as a non-browser client.
Here is how authentication is handled:
  1. You must register your smart TV app in Zoho API Console with the type "Non-browser application".
  2. Users install a dedicated Zoho ShowTime application on their smart TVs.
  3. When users launch the Zoho ShowTime application on their smart TV, they are prompted to authenticate with their Zoho ShowTime account.
  4. When they successfully authenticate, Zoho Accounts sends the grant token to your app, along with the user-code, device-code and verification URL,The user must go to this verification URL on a browser and enter the user-code to grant permission to the app.
  5. Meanwhile, your app must poll the accounts server using the grant token to check if the token has been received.
  6. When the user enters the user code, Zoho Accounts sends the access token to your app.
  7. Your app can then use the access token to make API calls to Zoho. Your app must take care of token storage and renewals.

Here is the protocol flow. For more details, refer to this doc.


5. Mobile-based applications

You must use this client type when you have developed an app exclusively for mobile devices. The protocol flow is similar to server-based application where a browser session is required for the users to authenticate.



Similar to server-side apps, mobile apps also need to handle redirection, token generation and storage.
If you use any of our Mobile SDKs, the SDK itself handles token generation and storage.

We hope you found this post useful. Let us know your thoughts in the Comment section or write to us at support@zohocrm.com.


Cheers!

    • Sticky Posts

    • Kaizen #217 - Actions APIs : Tasks

      Welcome to another week of Kaizen! In last week's post we discussed Email Notifications APIs which act as the link between your Workflow automations and you. We have discussed how Zylker Cloud Services uses Email Notifications API in their custom dashboard.

    • Kaizen #216 - Actions APIs : Email Notifications

      Welcome to another week of Kaizen! For the last three weeks, we have been discussing Zylker's workflows. We successfully updated a dormant workflow, built a new one from the ground up and more. But our work is not finished—these automated processes are

    • Kaizen #152 - Client Script Support for the new Canvas Record Forms

      Hello everyone! Have you ever wanted to trigger actions on click of a canvas button, icon, or text mandatory forms in Create/Edit and Clone Pages? Have you ever wanted to control how elements behave on the new Canvas Record Forms? This can be achieved

    • Kaizen #142: How to Navigate to Another Page in Zoho CRM using Client Script

      Hello everyone! Welcome back to another exciting Kaizen post. In this post, let us see how you can you navigate to different Pages using Client Script. In this Kaizen post, Need to Navigate to different Pages Client Script ZDKs related to navigation A.

    • Kaizen #210 - Answering your Questions | Event Management System using ZDK CLI

      Hello Everyone, Welcome back to yet another post in the Kaizen Series! As you already may know, for the Kaizen #200 milestone, we asked for your feedback and many of you suggested topics for us to discuss. We have been writing on these topics over the

    • Recent Topics

    • Related Lists filter

      I have Contacts showing in our Accounts module. I customized the Contacts module with an Employment Status field, with the following picklist options: "Primary Contact", "Secondary Contact", "Active Staff(not a main contact)", and "No longer employed".

    • Standalone custom function not generating logs

      Why dont't standalone custom functions generate logs when the're called from another function? I have some functions (workflow, buttons and blueprint) that have common parts, so I put that part in a standalone function which is called from the others.

    • Automated log-out/session end

      I'm concerned about security of our data. Is it possible to set an automatic time-out for user sessions on Zoho CRM, after a certain period of inactivity or when the session reaches a certain duration (12 hours perhaps)? 

    • Add "Reset MFA" Option for Zoho Creator Client Portal Users

      Hello Zoho Creator Team, We hope you are doing well. We would like to request an important enhancement related to Multi-Factor Authentication (MFA) for client portal users in Zoho Creator. Currently, Creator allows us to enforce MFA for portal users,

    • Support Bots and Automations in External Channels

      Hello Zoho Cliq Team, How are you? We actively use Zoho Cliq for collaboration, including with our external developers. For this purpose, external channels are a key tool since they work seamlessly within the same interface as all of our other channels

    • Urgent Security Feature Request – Add MFA to Zoho Projects Client Portal Hello Zoho Projects Team,

      Hello Zoho Projects Team, We hope you are doing well. We would like to submit an urgent security enhancement request regarding the Zoho Projects Client Portal. At this time, as far as we are aware, there is no Multi-Factor Authentication (MFA) available

    • Creator HTML page refresh

      Hi, I have added around 5 different html snippets in single creator page. I understand, I can refresh the entire page from page script using Navigational URLs https://help.zoho.com/portal/en/kb/creator/developer-guide/others/url-patterns/articles/navigational-urls

    • Zoho Desk - Custom Module Related List Columns on Tickets

      I have a custom module in Zoho Desk called Asana Tasks, each task has a lookup to a Ticket. On the Ticket I want to see the columns of the Asana Tasks in the related list . Is there a way to do this? Right now it just has the name of the record and I

    • Google Analytics import data inaccurate (as of October 11, 2025)

      We have Zoho Analytics connected to GA4 to import daily event data. This has been running without issue for a couple of years. However, a month ago we started noticing discrepancies. All data until October 10 lines up perfectly - October 11 onward is

    • What is your opinion of the new UI?

      Hi Everyone, I would like to see what everyone thinks of the new Zoho One Dashboard. I don't get it, but perhaps I'm missing something. What are your thoughts?

    • Zoho mail to Teaminbox

      Hello, We're searching for new mail program. Now I'm testing a bit with zoho mail and team inbox. My findings in the research: Pop mail throught zoho mail is almost instant. Any pop or imap via external provider takes a couple minutes to 15 minutes before

    • What are the OAuth scopes needed to access the Zoho MCP server?

      I think I'm authenticating with the MCP server endpoint successfully using a bearer token but I can't successfully initialize an MCP session. I'm using the official MCP Python sdk (https://github.com/modelcontextprotocol/python-sdk). I get as far as here

    • Account blocked for IMAP use

      Hello, My email client (Evolution) can't sync mail anymore. It gives the error: "Your account is temporarily blocked for IMAP use. This may happen if you exceed the maximum number of simultaneous IMAP connections allowed. Kindly try again after some time."

    • Is SMTP included in the free plan?

      My client has a Zoho Mail Free 14 day trial that ends tomorrow. She has set up a domain email address with SMTP on a third party app and is wondering if it will continue working once her plan downgrades to the free forever plan. Thanks

    • Zoho mail issue.

      I have verified my domain ohhoexpress.online by adding necessary TXT and MX records. But when I am sending email to any external email id, it is showing as zohomail.com. Also while I am sending mail to internal mail id, it is saying user not found whereas

    • My email is blocked from sending

      I get this message when I try to send any message .. > Unable to send message, Reason 554 5.1.8 Email Outgoing Blocked We have urgent emails to send and the issue continues to persist from yesterday. Please help us with this issue as soon as possibl

    • [WEBINAR] Smooth year-end closure with Zoho Books (KENYA)

      Hello there, This webinar is for all Kenyan businesses looking to wrap up their financial year smoothly! Join our free session to learn how Zoho Books can simplify your year-end process. What to expect from this webinar: - All the latest updates in Zoho

    • cannot recieve or send emails

      we are not recieving or cannot send emails.Shows sysytem error

    • Zoho Sites - contact us form

      I have added a contact us form to my website. I wanted to change the layout so I deleted the section of Contact Us form. When I again try to add the section of Contact Us form, it shows error that "This form already exists on this page."  I am unable

    • switching from POP3 to IMAPI do I need to change settings in Web email?

      hi so I am using Outlook with My Zoho mail, also have Verizon email /AOL. they no longer support POP3 and said imapi is much better, so I want to switch my ZoHo to imapai. I googled and it said i need to change it in my account....i looked at my account

    • What functionality is new in the Z025 Spaces UI dashboard compared to the previous Zoho One dashboard?

      My company is interested in creating a revamped dashboard this coming year, and are trying to weigh different platform options. The new Spaces UI is said to be a more "feature-rich" dashboard experience than the previous. Could a developer please explain

    • Collections Management: #5 Convenience on Offer, using Self-Checkout

      "Is this the right page? Oh, now, it wants my address again. Why am I being redirected?" These were the exact thoughts running through Karan's mind as he tried to subscribe to an application he genuinely liked. He clicked "Buy Now", expecting a quick

    • Uploading a signed template from Sign to Creator

      Good day, Please help me on how to load a signed document back into Creator after the process has been completed in Sign. Below is the code that I am trying, pdfFile = response.toFile("SignedDocument_4901354000000372029.pdf"); info pdfFile; // Attach

    • PROBLEMA

      Salve, non riesco a inviare email, e mi esce una tabela errore temporaneo. come posso risolvere il problema ?

    • Tip #50- A Closer Look at the Unattended Access Dashboard- 'Insider Insights'

      Having complete visibility and quick access to everything you need certainly makes managing multiple remote devices a lot easier, and that is precisely what the Unattended Access Dashboard in Zoho Assist is designed to offer. Once you go to the Unattended

    • How to update custom multi-user field in Zoho Projects?

      I'm trying to update custom multi-user fields in Zoho Projects via a Deluge function in CRM. The code I have so far is below. It works for updating standard project fields and single-line custom fields, but it does not work to update multi-user fields.

    • Tip of the Week #75– Manage your social media messages from a single shared inbox.

      Are you tired of jumping between apps or browser tabs to reply to your business's Facebook and Instagram DMs? Handling customer messages on social media might seem simple, but switching between multiple platforms can easily lead to lost messages, duplicate

    • Zoho Map integration tasks have changed - you need to "Locate all instances of Zoho Map integration tasks in your Deluge scripts by searching for the v1 marker... before 16 January 2026"

      The Zoho Map deluge integration task has been changed (as at 21 October 2025) to provide a more structured, JSON-like response. This change affects all three Zoho Map integration tasks (Geocode, Reverse Geocode, and Distance Between). More details can

    • Using files from Zoho CRM in Gemini/ChatGPT/Claude

      Hi all, I’ve got subscriptions to Gemini and a few other AI tools which I use for tasks like data enrichment, email composition, etc. In our workflow, we often receive various documents from clients — such as process workflows, BRDs/requirement documents

    • Zoho Analytics & Zoho Creator - Modified Time value

      I'm trying to use the Zoho Creator system field 'modified time' in Zoho Analytics, but it's consistently showing 12 hours 'out' In Zoho Creator In Zoho Analytics Is this a constant difference that I just need to correct with a timezone change - or is

    • Zoho CRM - Option to create Follow-Up Task

      When completing a Zoho CRM Task, it would be very helpful if there was an option to "Complete and Create Follow-Up Task" in the pop-up which appears. It could clone the task you are closing and then show it on the screen in edit mode, all the user would

    • Portal For Different Apps

      I found some older threads on this but didn't see anything very recent. I'm new to Zoho One so forgive me if my terminology is off a bit. I was hoping set up a single point of entry into Zoho One. So, many of the apps could be found in one single place

    • Calls undetected

      Zoho Voice records indicate my last call ended at 6:00 PM. All incoming and outgoing calls occurred between 6:00 PM and 7:00 PM.

    • Unable to Select Authenticated Domain as Sender

      We’ve already authenticated our domain, but it’s still not appearing in the sender list when we try to run a campaign. Could you please check what might be causing this issue?

    • Forever FREE Business Email with Zoho Mail

      Forever FREE Business Email with Zoho Mail: is it available?

    • Zoho Projects - Project Details on the Project Menu

      Hi Project's team, I've helped may businesses setup and use Zoho Project and one thing I see time and time again is confusion on where to find the Project Details information. I would be much more intuitive if Project Details was on the menu before Dashboard.

    • Introducing WhatsApp integration in Bigin

      Greetings! In today's business landscape, messaging apps play a significant role in customer operations. Customers can engage with businesses, seek support, ask questions, receive personalized recommendations, read reviews, and even make purchases—all

    • Zia Conversation Summary: Context at a glance for every customer interaction

      Hello everyone! Every customer conversation tells a story—but in CRM, that story is rarely in one place. A sales rep moving between multiple leads has to reopen long email threads, check call remarks, and revisit meeting notes just to remember what was

    • Zoho Projects - Show Task List as dropdown field on Task records

      Hi Project's Team, I noticed today that there is no field on a task record related to the task list it belongs to. A dropdown would be helpful for quickly moving tasks between lists while in a task. I know that you can go to "Other Actions" and choose

    • Changing the Default Search Criteria for Finding Duplicates

      Hey everyone, is it possible to adjust the default search criteria for finding and merging duplicate records? Right now, CRM uses some (in my opinion nonsensical) fields as search criteria for duplicate records which do nothing except dilute the results.

    • Next Page