While standard games did not typically feature QR codes (as the DS hardware lacked a built-in camera until the DSi), QR codes became a staple of the Nintendo 3DS era for sharing user-generated content and accessing the Nintendo eShop .
Some late-era DS/DSi and 3DS titles used QR codes on physical marketing materials (like manuals, posters, or website printouts) to unlock special items: Cars 2: The Video Game nintendo ds games qr codes
If you want to use QR codes to enhance your DS gaming experience legally, follow this path: While standard games did not typically feature QR