Apple staff are probably scrambling to have it taken down right now, but Floppy Cloud, a file management app, is (not so) secretly also an emulator that runs old-school Nintendo games.
If you ‘obtain’ an NES or SNES ROM and throw it into your Dropbox account, then connect that account to Floppy Cloud, you can open the ROMs and play the game right there on your iOS device. It isn’t the first time we’ve seen this kind of thing – arcade machine emulator MAME emerges in some form every now and then – but full marks to the developer of Floppy Cloud for the creative approach here – even if it’s unlikely to last long on the App Store.
It’s not just Apple that frowns on using unauthorized game ROMs – Nintendo does too. It would much rather you spent money on official versions of its old titles via its eShop.