NES.app lets you play Nintendo games on your iPhone. It is a fully functional, feature-rich Nintendo emulator.

NES.app uses an emulator core we call NESCore, which we’ve forked from pNESx and InfoNES and re-engineered as a highly-portable and high-performance Nintendo emulator core.

In order to use NES.app, you will need ROM images of Nintendo games. ROM images are files containing the dumped instruction code from a physical cartridge. In many cases, you are legally entitled to posess a ROM imageof any game that you presently own. ROM images for NES are widely available online, or with the appropriate hardware, you can dump them yourself directly from the cartridge.

NES.app started as a fork of iPhoneNES v0.01, but has been completely rewritten to run very fast, and with many additional features including sound, multitouch support, full-screen, landscape mode, game genie codes, saved games and much more. It now contains zero code from the original iPhoneNES project.

Changes:

[nervegas] Fixed white noise channel frequencies
[nervegas] Fixed PCM DMA
[jordan] Added PAL support, use filename (E) unless marked in header (Many are not marked in the header)

http://iphone.natetrue.com/nesapp/