How can Integrate a new app on Quickbooks to be on the list of the apps can be sync

Welcome to the Community space, empirepainting21. I know where you can find the best help to integrate a new app that syncs with Quickbooks.

We have a dedicated Intuit Developer Community where you can interact with fellow developers, product experts, and engineers about software, APIs, or developer license-related queries. They have all the necessary tools and resources to answer your concerns. I'll show you how: 

1. Head to the Intuit Developer page.
2. Select the Sign In or Sign Up button to create an account.
3. Choose from Documentation, API Explorer, Basic accounting, and App publishing.
4. You can also scroll down to Contact us.

In case you're interested in seeing the supported apps you can connect, check out this page: Apps that work with QuickBooks Online.

Furthermore, save this link for subtopics and help articles that will aid you along the way: Account management.

I'm still ready to back you up if you have other questions about QuickBooks. I'll keep the thread open so you can comment back. Have a great day!