Okay, I ponied up out of curiosity. Do not download this app. It does not work as advertised. It is slow, buggy (even the table display on the home screen has impressively bad rendering glitches) and, worst of all, it is not capable of loading any ROM files I tried it with -- things that all other NES emulators load fine.
I was able to load several roms with no trouble (though the UI could use some work). The performance was fine (3GS here) and the accuracy of graphics and gameplay seemed good, but the sound was very glitchy. Hopefully it can be fixed in an update before Apple boots it from the store.
Ultimately the biggest problem with this is that the touchscreen just isn't as good as physical buttons for the kinds of games that the NES had.
I loaded the ROMs from my mac mini via the web sharing feature of OS X (Apache). All the ROMs I tried worked the first time. Some ROM formats may not be supported; the ones I used had a .nes file extension.
