Receipt Bank is one example of an application that can be integrated with QuickBooks Online to increase efficiency.
You can use your phone to snap cash receipts, or forward emailed bills to Receipt Bank, where these can be processed and uploaded into QuickBooks online, with the images for you and your accountant to view later.
Satago is an add on that does credit control and accounts receivable management. You will find out your customers credit scores, how many days late they pay their suppliers on average, before you agree to do business with them. You can automate the process of chasing your customers for payments using customised, escalating email reminders to get your customers paying you as quickly as possible. Satago enables you outsource your credit control department to some software!