Mobile application without direct authorization \ registration

UX \ UI professionals. The question connects both the user experience and data security.

We are going to build the app, where the user is going to pay for the services.

He should enter his email, phone and info before the purchasing and we're going not to implement the authorization within the app.

So, after the user enters his email, we'll check either his account exist or no. If no, we'll create, if not - authorize, but in the background, not showing this to him.

We need to authorize him only to check his purchases history, data for the credit card won't be saved by us.

How do you think, is it preferable method? What aftergrowths it can cause? Thank you.