Also disappointed
Response from developer
Thank you for your review! The app is designed to flow to the next box after you enter two digits. You might have had an issue when entering just a single digit. For example, If you type "1", our app doesn't know if you mean "1" and you're done or if you mean "10". An easy solution to this is to type 01, 02, 03 and then it will flow from box to box seamlessly. Let us know if this works for you.