Play Nintendo DS games on non-jailbroken devices with the nds4ios emulator | 9to5Mac
The app gets around Apple’s restrictions by using an enterprise provisioning profile reports TourchArcade. This is normally meant for businesses to distribute apps to company employees, but nds4ios is exploiting it as a way to enable widespread app distribution. "

I'm probably not alone in thinking that the App Store is now completely overcrowded with junk that would likely not be clogging the pipes if there were simpler ways to do ad-hoc distribution.