How do I link a diary app

Glad to have you here in the Community, @vanityfurjsy.

QuickBooks Online (QBO) allows you to integrate or link third-party applications and software.

In your QBO account, you can go to the Apps menu and search for Diary App. From there, you can verify if the Diary App integrates with QBO.

If you have further questions about Diary App, I recommend contacting their customer service team.

Please know you can continue to reach me here with any additional questions. Thanks for coming to the Community, wishing you continued success.