Query related to in-app purchase

We are developing a tipping system that allows users to collect tips through our application based on their chosen subscription plan. Our application offers two key features:

Tap to Pay – Allows users to receive tips using Tap to Pay. Payment Profile Creation – Enables users to create multiple payment profiles.

Both features are exclusively available to premium users. If a user selects the free plan, these features will be visible but not selectable.

Question: Our main concern is whether integrating In-App Purchases (IAP) is mandatory for the subscription purchase flow or if we can use alternative payment methods such as Stripe instead.

Query related to in-app purchase
 
 
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