Multiple new users

[Max4444]

I have a product to which i want to pre print a QR code with each product.
When the user downloads the app, they scan the QR code.
My issue so far is I need a new email address per new account.
Is there a better way to set something up, where i can limit the number of notifications?

Ie, i sell a black box. Client downloads the app in gest mode, they scan the QR code.
I am the one paying for the account, my customer pays me for the rental of the black box.

I am open to ideas.

[admin]

there is no way to create new account automatically.
Better is your users create ther own account and enter the pushsafer credentials in your hard- or software, to send the notifications.