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 called NESCore.
Free NES Roms to try out can be found here: //files/nes/
Changes:
[jonz] Added case-insensitive sort of files, bookmarks, and saved games
[jonz] Added support for left-handed landscape mode (turn clockwise)
AEP-Emu (DE/EN)
DMG Page (DE)
Indie Retro News (EN)
Retroguru (EN)