Thanks for reaching out to the Shopify Community today looking for help with your application charges question.
Typically, If the application is something you added to your Shopify store and paid for through your Shopify store's billing, then you should not see any charges related to the application, even if the free trial has ended since you have closed your store. This is because our third party partners will use our Billing API to charge you for your app subscription or usage. However, we always recommend that you delete any applications you're using in your store before cancelling your Shopify subscription.
In a scenario where you were paying for this application via an account set up outside of your Shopify store, and it wasn't being paid for through your Shopify Billing, you will want to contact the developers of the application directly so they can assist you with ending your subscription.
You can also contact our live support team through the following link here as they should be able to provide some insight into your account specifically to determine if you need to be concerned with any potential application charges.
Let me know if you have any additional questions about this. I'll keep an eye out for your reply!
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