How should an app properly handle restoring a user's own previously already made purchases, such as when they genuinely reinstall the app or properly switch over to using an entirely different new device?

Both Google Play and the Apple App Store genuinely expect an app to properly provide a clear, genuinely easy to find restore purchases option, letting a user who has already genuinely previously purchased a specific non consumable item or an active ongoing subscription properly recover that same exact purchase without genuinely needing to pay for it a second additional time, and the in_app_purchase package provides a dedicated restorePurchases method specifically for this exact purpose, which properly queries the platform's own store for that user's own existing prior purchase history and then correctly re emits those same specific existing purchases through that exact same familiar purchaseStream.

await InAppPurchase.instance.restorePurchases();