This is a brand new feature from Microsoft and Xero, for Xero and Office 365, and I’ve just tried it out and it could be useful for a lot of people.
The App allows Office 365 to talk to Xero, presenting you the account status/details from Xero in 365. This saves you having to go into Xero to check on details.
So there you are, about send an email to someone, and with a click or two within 365 you can see whether this person owes you money and how much (or whether you owe them and how much!).
More info and download the app from click here