In our iPhone app it is really easy to add cash transactions on the go! Just click on the "Add a Cash Transaction" button when you first open the app and put in your passcode.
Alternatively, you can click on the button below in the Summary or Inbox tab of the Money Center.
If the cash you used came from a withdrawal you made and the withdrawal is foldered in your Inbox in your "ATM/Cash" folder, you can indicate this on the "This Cash Came From An ATM" slider. You will then see the total of your "ATM/Cash" folder fall by the amount of the cash transaction. This ensures that nothing is double counted in your Inbox!