Convert E-Commerce Site to Apps

I run an e-commerce webpage that sells access to online tests. The site already charges users a flat $12 via Stripe before granting entry. I now need this experience packaged as:

• a PWA that continues to live on Netlify
• a native iOS build for the Apple App Store
• a native Android build for Google Play

I need to know how much it would cost to do this work.

Key requirement for Apple: the $12 must be paid on my website first—no in-app purchase. When the iOS app opens, it should simply verify the user’s existing payment (token or login) and then unlock the content. Android can mirror the current Stripe flow, while the Netlify version should behave exactly as it does today.

Please handle everything from code refactor, payment verification logic, and user authentication through to store-ready binaries and final submissions. Technologies such as React, React Native/Expo, Stripe API, and Netlify Functions are welcome, but I’m open to alternatives if they achieve the same seamless result.

Deliverables
- Source code for web, iOS, and Android builds
- Live deployment on Netlify
- Approved listings on the Apple App Store and Google Play Store (TestFlight / closed testing is fine for initial sign-off)
- Setup documentation covering payment verification, env variables, and update procedure

Acceptance criteria: a user pays $12 on the site, signs in on any platform, and instantly accesses the tests; both apps clear store review without requiring in-app purchase for iOS.