Quickbooks Online Integration with VTiger is an extension connecting VTiger to QuickBooks and enabling bidirectional synchronization of Customers (Organizations/Contacts), Invoices, Payments, Quotes (Estimates), Sales Orders (Sales Receipts), Purchase Orders, Vendors as well as Items (Services & Products). An easy to trigger option to synchronize data manually or on the schedule. It supports custom fields on the invoice as well as customer (flexible mapping).
How to Synchronize Invoices
Go to Menu > Settings > CRM Settings > Extension Pack > Quickbooks Online.
In Invoice Tab you can map invoice fields into Quickbooks.
It also supports custom fields.
Create an Invoice and add a product and service.
You need to check box “Sync to Quickbooks” and that will automatically add this record to the queue to be synced with Quickbooks.