Your end-users will pay via the apple app store/ google play store if they pay on mobile. Or via credit/debit card for PassionPayments. For Google, Apple, and PassionPayments purchases, since you will be setting this up, payments will be deposited directly to your registered bank account.
You will also have the added benefit of being able to set up payments outside of the app store. For instance, if you have your own web check-out, you can link it to your app so that your end-users pay directly using your web check out and you get the payment faster and save on the app stores processing fees.