Good app that does exactly as advertised, while providing enough flexibility for our ground staff. Still missing a couple of features and there is some awkwardness due to Shopify restrictions, but the developer is always very useful and reactive.
I'm using this app to give e-vouchers to my customers and so far, it has been a seamless experience. The interface in simple and intuitive. Also, the customer service is top notch. I would really recommend this!