Vify Order Printer PDF Invoice

Was looking for a simple clean and reliable app to download and send invoices to customers as Shopify is weak in that dept. Saw the reviews on this one and thought will give it a try.... I installed it and within minutes it was customized and working and doing exactly what I wanted to do. I had a couple of questions so messaged support and was blown away they answered in about 2 mins !!! I just cannot believe this app is free. Developer has offered as well to make a couple of changes for me so my customers can log in and download their own invoices Absolutely phenomenal service thanks