Thank you for posting here in the Community,JustHEF.
There are two ways to integrate third-party applications with QuickBooks. You can connect apps with our system where QuickBooks initiates the integration to the app. While the other way is for the third party to initiate the integration to QuickBooks.
You can also click this link where you can find apps that is integrated with QuickBooks: https://apps.intuit.com/app/apps/home.
Please let me know if you need further clarification about this, or if there's anything else I can do for you. I'll be standing by for your response. Have a great day.
