I've recently launched a business with a colleague of mine. We're branching into another avenue and would ideally need an app for both ios and Android that a user can create an account and has to submit some form of ID that gets manually approved by one of us (for now) - this is for age verification.
Once approved, they can link their account to a debit card/paypal etc and top up their balance/buy credits.
Then the user can either scan a code on a vending machine i.e. QR code OR receive a user unique pin that they can key in and redeem a purchase.
If interested, can discuss in much more detail.