I like the simplicity of this app - both for the customer and the back-end interface. It only works for products though, and I would like to be able to embed the code into a Shop Reviews page because each of my products are unique and after being sold are removed (and therefore the reviews will also be removed). Also, it would be great if the social share options were available to customers who submit.
As for automatic emails with coupon codes, I prefer to manage that within Shopify and personally contact each of my customers, so I'm fine with the fact that the app doesn't offer this. Again, I like its' simplicity and ease of use, and particularly that the interface stays within the Shopify admin panel.
Nice app, I look forward to seeing the above updates if possible.