How to offer membership to a gym or club from the app

We have a cycling studio/ bike gym. We offer classes and you need a membership to reserve a class. This is very similar to a gym membership.

I just need to make sure how the payments will work.

According to the guideline 3.1.3(e) Goods and Services Outside of the App I think we can offer payments with a traditional credit card entry.

Is this so?

Because in the forum I found answers stating you need to use in-app-purchase.

I really need to make sure before beginning the app development.

Thank you.

How to offer membership to a gym or club from the app
 
 
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