Temper was originally developed for the South Korean GamePark 2X handheld and ran ROM- and CD-Based titles designed for NEC's 16-bit system, which was a smash in Japan (as the PC-Engine) but enjoyed modest success in the West under its Turbo-fied moniker. As you can see from the embedded video, the emu is already plenty impressive. Unlike its GP2X counterpart, there's no support (yet) for CD-based game images, but compatibility with TG-16 ROMs (if you don't own the game, don't download em, 'kay?) is said to be high. Like previous emulators ported to iPhone, the retro console's controls are recreated on the touch screen.
Apple is expected to launch its "2.0" refresh of the iPhone along with the iPhone App Store in just a couple of weeks, and we'd be jazzed to see a proper Virtual Console-esque suite of "sanctioned" emulators offered for download via the service.
Apple iPhone 6
Apple iPhone OS 2.0
NEC TurboGrafx 16