You can create a single App Store QR Code which will redirect users to your app on their respective app stores.
To create an App Store Links QR Code, follow the steps given below:
Choose the App Store Links from the recommended category
Enter URLs of the app for iPhone, iPad, Android, Windows, and Blackberry
Click on Create QR Code
You'll see a dialog box asking you to name and save the QR Code. Enter the name and click on Save
You can then proceed to Design and Download your QR Code
You can edit the URLs saved in your App Store QR Code anytime you want, without having to change the QR Code. You can edit your QR Codes in the Saved QR Codes section of your account.