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Rewardify does what it says - it creates store credit for customers and lets you import store credit as well. It also has a suite of features that would be quite useful for wholesales or businesses that are reliant on store credit as a marketing tool. Having said that, it did not suit our purposes. Using store credit cancels out the ability for the customer to use discounts, because Rewardify saves the store credit as a discount, and Shopify does not allow discounts to be stacked. I also found their user interface to be unintuitive, and their documentation unhelpful.