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

Changes:

[jonz] Fixed preference labels and removed show selection of buttons
[jonz] Changed main ROM list to be section list (like contact list)
[jonz] Removed “can delete roms” feature
[jonz] Significant code cleanup

http://www.zdziarski.com/projects/nesapp/