When using In-App purchasing on Android, the Subscription product is failing to register.

The issue is in qtpurchasing/src/android/src/org/qtproject/qt5/android/purchasing/QtInAppPurchase.java:256 which contains:

Bundle bundle = m_service.getSkuDetails(IAP_VERSION, 
m_context.getPackageName(), 
"inapp", 
productIdBundle); 

The official documentation at https://developer.android.com/google/play/billing/billing_reference.html#getSkuDetails states that Value must be “inapp” for an in-app product or "subs" for subscriptions.

The attached diff file can be used to workaround this issue.