Furthermore, Flipnote Studio 3D was region-locked. A Japanese 3DS could not download the US version without custom firmware. For years, legitimate access required jumping through hoops (like being a Japanese Club Nintendo member).
Warning: The official Nintendo servers for these QR codes are gone. However, if the QR code points to a direct download from a fan server (via a custom homebrew launcher), it can still work. flipnote studio 3ds qr code