To add the app to SharePoint environment, Office 365 administrator privileges are required
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Download Forms Pro to Complete the App Installation
Download the Forms Pro free trial version
Add Forms Pro to Your Apps section in SharePoint
Start the app from the List's Ribbon pane
You are 2 minutes away from the exciting Forms Pro experience:

The Forms Designer allows you to transform any SharePoint list form into a user-friendly layout with additional blocks and tabs.

All you have to do is to drag and drop the elements from left to right.

As a SharePoint administrator, you can assign permissions to a user or a user group to particular form fileds.
Forms Designer Overview
Forms Pro Quick Installation Guide
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At your Office 365 admin center, get to the App Catalog library taking the path:
Admin section » SharePoint » Apps » App Catalog

You can navigate to App Catalog by a direct link https://[your_domain_name] if your Office 365 subscription plan allows to.

Go to Settings on the site where you are going to add Forms Pro and click Add an app.

On the Your Apps page, click From Your Organization.

Then click the Forms Pro for Office 365 by Virto icon and click Trust It to add the app.

From now on, the Virto Forms icon is displayed on the Ribbon pane, so you can start the app directly from your Lists or Document Libraries.

Alternatively, you can start the app from Site Contents of the Site, where you installed the app, by clicking the Forms Pro icon.