The app focuses on acquiring new customers for your store. Since the customer is new, you would offer a significant discount to entice him/her. In addition, it is likely that the new customer would make a single purchase. This is because the customer is just trying out the store. Thus, it makes sense to offer a discount based on a single purchase, automatically apply the discount and bring the customer to check out immediately.
First, we need a discount code that limits the customer to 1 use only. This is because it should be a special discount just for new customers. If it is can be used more than once, it would not be special. Second, we need the discount to be active and no end date. This makes it easy for management. Do not worry about control since it is already limited to 1 use per customer and you can disable the discount code when you uninstall the app. Please do not let use the discount code elsewhere. This would make it easy to check on the effectiveness of the app.
It can be any value from 10 seconds to 60 seconds. It depends on how aggressive or conservative you want to be. Please consider it carefully together with the discount and strike a balance. If you have Google Analytics installed, you can use the avg. session duration of your channel/landing page to help you make a decision. Otherwise, leave it to use the default value.
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