The Notifications box gathers all your invoicing reminders and calendar invites into one place.
The tabs in the Notifications box
SCHEDULED PAYMENTS = Scheduled payments that are waiting for action. Scheduled payments will appear in the Notifications box according to their due dates.
PURCHASE INVOICES = Purchase invoices waiting for action.
SALES INVOICES = Sales invoices that are past due.
CALENDAR INVITES = Calendar invites you've received that are waiting for action (Accept/Deny)