This would work unless, the client wants to monetize via freemium model; in that case an IAP with native app would be far more intuitive than a web app as integ

This would work unless, the client wants to monetize via freemium model; in that case an IAP with native app would be far more intuitive than a web app as integrating a payment gateway which accepts global payments (Stripe is not available in all countries) is harder than integrating In app purchase on iOS or android.