Build me a unity 3d asset, serial number verification method

my project is an unity 3d learning game working on both IOS and Android, I want to sell it as a gift with a printed book, and every book has a qr code. this qr code is needed to be use to activate the app. what I need to be done: * activation scene to activate the app * using qr code reader. * each qr code , activate only one mobile device.