Hello, thank you for the answer but Forgive me, I still don't understand why I repeat them, on the app there are events that have their own price, it's not precise or fixed so how can I specify the price on in-app purchases? Unfortunately I look at all the apps they have developed, it is to understand how they did it and why they were published!? The SuperEnalotto app has a payment service not including Apple Pay but PayPal, Strike, Stripe, etc and as specified on in-app purchases and it is outside the app, this is what makes me doubt... but for Is there a more precise and easier to understand page? like on YouTube or an example?