I think the biggest problem here is that your target market isn't willing to pay for this problem to be solved.

I'm not sure exactly what your app does from the screenshots, but it looks like it's a way to email a receipt for a purchase to a customer? Wouldn't the business owner probably want this feature integrated with their Point of Sale system or something else, rather than retype everything into their iPhone or iPad? Or is this meant to replace a Point of Sale system?