CRM cards are micro-applications that live on your CRM record pages. They extend HubSpot's functionality beyond what you can do with out-of-the-box functionality. With CRM Cards, your team can complete tasks that would usually require them to access
Your most complex business cases, built on top of HubSpot’s UI.
There are three types of problems that CRM cards are excellent solutions for:
Accessing and Actioning Data from External Sources
These types of CRM cards show you data from outside of HubSpot or allow you to action data by adding or editing data that exists elsewhere.
For example, a Sensitive Information Retrieval card allows you to retrieve credit card information that is stored in a PCI-compliant vault outside of HubSpot.
Creating a Customized Output Based on a Series of Inputs
These types of cards ask a set of questions and, based on your answers, provide you with a response.
For example, a CPQ card asks you questions about products, bundles, and pricing, and provides you with a custom-built quote.
Record-Specific Reports
These types of cards will show reports that are specific to that contact, company, deal, or other record.
For example, a web visits report could show you a timeline of a single contact’s website activity.
Links for more information:
https://developers.hubspot.com/blog/how-to-set-up-and-use-hubspot-crm-cards
https://developers.hubspot.com/docs/api/crm/extensions/crm-cards
https://aptitude8.com/the-hubspot-crm-card-playbook#:~:text=CRM%20cards%20are%20micro%2Dapplications,multiple%20systems%2C%20entirely%20within%20HubSpot.