I need to retrieve the recurring charge to run some logic, but my app is not published yet so it is unable to find the recurring "test" charge and then when I try to add my app to a real store that is not possible because the app is no published.
I don't understand how there can be API calls which do not work in test mode!
All these do work when "test": true
When you create a recurring application charge, you'll get "id"
You redirect the merchant to "confirmation_url" and then if they accept, shopify will redirect them back to your "return_url", with the charge_id as a parameter, something like "http://super-duper.shopifyapps.com/?charge_id=1029266957", if I remember correctly.
Using that charge_id, you can GET information about a specific recurring_application_charge_id
or if you want to see a list of all recurring applicatiion charges:
I think that's the flow ...