The best SNES Emulator for iOS which is compatible with all generations of iPhone, iPad and iPod is SNES9x EX. Based on the latest SNES9x core it has full compatibility and best of all it is free. This is not to be confused with SNES4iPhone and iSNES both of which are paid for apps. However as these are largly based on SNES9x themselves it is better to go for the most direct port – SNES9x EX
One of the best features is the ability to use a Wii Remote to play your roms more accurately!