iPod 2g and before run ARMv6, after this runs ARMv7. Both devices can run ARMv6 code, so this is more desirable when porting. i386 is a subset of x86, which is what computers with Intel processors have. amd64 is the 64-bit subset of AMD processors. These two are completely different processors, so code compiled for these platforms WILL NOT run on iOS. Also, the file format for binaries on iOS is mach-o, which is what OS X executables are. This is a different format then the standard *nix file format, ELF. I believe that there are existing tools which can convert between these formats, but im not sure.