If you want to use other peoples' designs, you have to hack the QR codes with a program only for android phones. I don't design my own things, so I use that to have extra storage space. If you'd like the link I'm sure I can dig it up, my phone has disappeared somewhere in the depths of my room xD; It's really absurd that Nintendo doesn't allow this "legitimately", however, considering that they put up designs by "Someone" from "Anytown" and included dialogue for that? Makes zero sense to me.