After you enter the check number on the payment screen and hit TAB, it would be nice if it would go directly to the green PAY button to post the payment. Instead you have hit the tab button 4 times just to get to the green PAY button.
Suggestion: What would be really nice is, after you enter the check number you can just hit the enter button on the key board and than it would take you to the green PAY button and you can hit the enter button again. For me that would make it a smoother flow.