Note an important difference between iconv() and mb_convert_encoding() - if you're working with strings, as opposed to files, you most likely want mb_convert_encoding() and not iconv(), because iconv() will add a byte-order marker to the beginning of (for example) a UTF-32 string when converting from e.g. ISO-8859-1, which can throw off all your subsequent calculations and operations on the resulting string.
In other words, iconv() appears to be intended for use when converting the contents of files - whereas mb_convert_encoding() is intended for use when juggling strings internally, e.g. strings that aren't being read/written to/from files, but exchanged with some other media.
