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I have few questions regarding the in app purchase auto renewal. Our app uses "Auto-Renewable Subscription" product with monthly subscription. My question is how can we update the Subscription payment details in Database on each month when the auto recurring done in user's apple account. Hope this "verifyReceipt" API used to fetch receipt from apple server and it can be called only if user authorized their apple id. If so, how can we track each user's monthly subscription details in our server. We have to either run any API via cron or call the API each time when they open the app without authorize their apple id. Please let me know how you all implemented it..