I’m building a Flutter app with an account-based subscription model (users must log in).

Current implementation

• Android: subscriptions are purchased exclusively via Google Play Billing

• iOS: subscriptions are purchased exclusively via StoreKit (In-App Purchase)

• The app does not:

  • Link to external payment pages
  • Mention purchasing on other platforms
  • Encourage users to subscribe outside the platform

Subscriptions are tied to the user account on my backend. After validating receipts (Google / Apple), the backend grants premium entitlement.

Intended behavior

If a user:

• Purchases a subscription on Android
• Logs into the same account on iOS

They will automatically have premium access on iOS (and vice versa), because entitlement is synced server-side.

Both platforms still allow native in-app subscription purchases independently.

Questions

1. Under current Apple App Store Review Guidelines (especially section 3.1.x) and Google Play Payments Policy, is this cross-platform entitlement syncing explicitly allowed?
2. Have there been documented rejection cases where apps were rejected solely for allowing subscription access across platforms?
3. Does using a third-party subscription wrapper (e.g., RevenueCat or Qonversion), while still using StoreKit and Google Play Billing under the hood, introduce additional compliance risk during review?

I’m not asking about monetization strategy — only about Store policy compliance and review risk.

Any policy references or real-world review experiences would be appreciated.