In practice, most QR codes you see link to a .duc (DS save file) or a patch file. Scanning the QR with your phone just reveals a download URL.
Increased resolutions when played on emulators, or new texture packs 1.2.4. mario kart ds qr code
Here are the most in-demand codes. Disclaimer: Using save exploit QR codes will erase your current progress. Back up your save using a DS flashcart if you want to keep your old data. In practice, most QR codes you see link to a
To avoid confusion with other Mario Kart titles that do use QR codes: mario kart ds qr code
Use a tool like xDelta to apply the mod file (.xdelta) to your legal ROM.