I don't need Rattata's, Pidgeys, weedles and caterpies anymore, i assume it wouldn't be too hard to add the option to simply ignore the existence of certain pokemon.
Having just acquired MyGoBot, it had this feature plus a few others, so you may be able to get a good head start from there.
Having just acquired MyGoBot, it had this feature plus a few others, so you may be able to get a good head start from there.