I need to offer an upgrade option in my application to allow the user to go from a Monthly subscription to an Annual subscription.
Right now, I'm implementing this in Android, and I will implement in iOS next.
Google documentation mentions an getBuyIntentToReplaceSkus() API, but there seems to be no equivalent in the Xamarin.InAppBilling component. Nor is there something that might allow me to cancel the first subscription from within the app and then allow me to use the standard PurchaseProduct() api to purchase the new subscription.
How can I offer my Android customers an upgrade? I haven't looked into iOS yet - will I have the same problem there eventually?