Logic helps automate elaborate tasks by introducing custom rules to filter data or defer the execution of a few actions. You can even create your own logic element with custom functions. When used alongside app-based actions, these elements can make your flow more comprehensive.
The logic types available are Flow Control, Notification, and Custom Functions.
Flow Control contains logic elements that streamline your flow according to specific requirements of your business.
Set variable - Create a variable and assign it a constant value or the result of a formula.
Decision - Enable your workflow to execute different actions based on the conditions.
Delay - Delay task executions according to your preferences. There are two types of delay: Delay For and Delay Until.
Notification consists of logic elements that help you send notifications through your workflows.
Send email- Send an email from a verified email domain through your workflows.
Create your own function from scratch in Zoho Flow using Deluge script. Learn more
With Set Variable, you can create a variable and assign it a value. The value can be constant or the result of a formula.
For example, you can configure age=18. 'age' is the name of your variable and 18 is the constant value you assign. You can also configure age=${trigger.age+10}. The variable 'age' fetches a value from the trigger, adds 10, and stores the result.
To configure Set Variable:
You will now be able to map this value in the actions that follow.
For example, you can calculate the total price of a bundle in Zoho Inventory along with tax. The Set Variable fetches the amount from Zoho Inventory and performs the configured calculations.
Decision lets you branch your workflows to check for conditions and perform different tasks. Conditions are the rules you provide (e.g: Ticket Subject contains "issue"). You can provide as many conditions as you need, and define what the flow should do if a set of rules are satisfied.
For example, when a ticket is updated in Zoho Desk, depending on fields like subject or status, you can configure your workflow to perform different tasks, such as creating a task in Zoho Projects, updating a Google spreadsheet, or sending a Slack message.
To configure Decision:

The dropdown will only list the default variables provided by an application. If you need manually configured fields in an application from a trigger or action output, such as Custom Fields in Zoho Projects, you will have to use Set Variable to assign it to a new variable that will be available for all actions and conditions in the flow.
Output variables received from a webhook trigger should also be assigned to new variables using Set Variable to be used in conditions. Learn more
Delay postpones one or more actions in the flow for a time period or until a specified date. This means you can configure a part of the workflow to execute when it is triggered, and the other part to execute after a certain amount of delay.
For example, you can send an email 30 minutes after a form submission is made. Alternatively, you can send an email on February 20th to those who have registered for your event.
Note: You can use natural language to input dates and time periods into the Delay for option. For example, Flow will accept entries like 3 days, a month, or four weeks. Your current time will be used as the starting time for the duration. If you create a 3-day delay action at 2PM, it will be executed at 2PM three days from the date you created it.To configure Delay:
Click the Logic tab on the left side of the builder.
Drag and drop If else from Flow Control.
In the configuration window that appears, set the test conditions. You can add more test conditions by hovering over a test condition and clicking the + icon.
Note:
You can add different test conditions in the group or as many groups as required. Every time you add a group or a test condition, a dropdown with AND/OR will appear.
From our earlier example, if you need to check if the deal value is greater than $10000 and also ensure that the company size is greater than 100, you need to add two conditions:
Deal value > 10000 AND Company size > 100
Similarly, you can add groups of conditions to be compared with each other. When you add test conditions in the same group, the output of each condition in the group is evaluated sequentially to be the output of the entire group. To add a new group, click Add Group.
Add the actions to the bottom of the if else block for them to be performed when the conditions are not met, and to the right of the block for them to be performed when the conditions are met.

Let’s assume that you built a flow using the Entry Submitted trigger in Zoho Forms, where Email is one of the form fields. Each time a response is submitted, the email address from the form is mapped to the To address in the Send Email action.
Problem
In the use case above, even though your email address is verified, your domain is not, so emails will be sent from noreply@zohoflow.com. Your recipients may assume that these emails are sent from Zoho Flow because of the From email address and click on the malicious links sent via emails.
For Send Email notifications, you must verify the email address as well as the domain in order to send emails from your own email addresses. Only after the email address and domain are verified will the email address appear in the From dropdown and can be used to send emails from that domain. You can also configure the From field in the action to add a custom email address instead of the default noreply@zohoflow.com.
Provide the email address that you want to use as the From address in the Email address field and click Verify.
A One-Time Password (OTP) will be sent to the email address provided. Enter it in the verification code field and click Verify to complete the verification.
Note: If you do not complete verification, noreply@zohoflow.com will be used as the default From addressSign in to your domain host.
Go to the DNS records page of the domain and locate the option to add TXT records.
Copy the Host name, Domain SPF, and Domain DKIM and paste them in the TXT record.
Once you're done, click Validate.
Once the email address and domain are verified, you can view the domain and email address in the Mail Management section, which can be accessed under the Settings tab.
Important: Domain verification (using SPF/DKIM) is a one-time process. Once done, it applies across all Zoho apps, powered by the ZeptoMail API.You can view all the verified domains and email addresses on the Mail Management page.
To authenticate a domain, click Authenticate. Once it is verified, the status will change to Authenticated.
You can delete a domain or email address by clicking the trash icon. The deleted email address and domain will be deleted permanently. You can add them again, if needed.