Snes4iphone is a Super Nintendo emulator for the iPhone and iPod Touch. This port was developed by ZodTTD and the original source code was ported from Dr. PocketSNES. Though much of Dr PocketSNES' emulation cores were replaced with C/C++ alternatives to assembly cores provided. This is due to Apple using a specific register (R9) globally, disallowing many tightly written assembly sources to be used.