DoubleAgent can now accrue (or defer) the income from invoices for you. And similarly for bills.
Most people only encounter accruals when their accountant adds them at financial year-end. However they are helpful any time your invoice (or bill) covers more than one month's work, because they make your balance sheet and P&L more accurate.
If you are a SAAS company and you invoice your customers annually, accruing the income means your balance sheet and P&L will give you a much truer picture of where your business stands.
This is also known as revenue recognition.
You can read more in the docs.