Mobile App: Add Class to an Invoice or Estimate 1. Log in with your InvoiceASAP Username and Password. 2. Tap on Invoices (or Estimates) from the app's main menu. 3. Tap on the invoice (or estimate) you want to add the class to. 4. Tap on Edit. 5. Tap on the edit icon next to Terms. 6. Tap on the Invoice Class selector. 7. Select the class you want. 8. Tap Done. 9. Tap Save. Have more questions? Submit a request 0 Comments Please sign in to leave a comment.