This is really interesting.
By integrating the Mobile Time Tracker application (MTT) with the Xero app, you save a lot of time creating invoices or adding the client data manually in the Xero app.
Once the Xero application is integrated with the MTT app, you should create the scheduler in Salesforce for creating the Invoices in the Xero app and for syncing the contact details from Xero to the MTT application.