Third-party payment system for a parking app.

Hello everyone,

I am developing a parking app where users can find and pay for parking. Instead of directly paying with real money, users can reload their points or stars balance and then pay with that virtual money. Would using Apple's IAP be compulsory or can I integrate my third-party payment system within the app? If not, what if I direct the user to a website?

Thank you!

Third-party payment system for a parking app.
 
 
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