If there is already such an app, by all means do tell, I've been looking for one for ages. The idea is an app that would take a 4th gen pkm file and update it for use in 5th gen pokesav, that is, fix pokemon and trainer names, location, delete held items and 4th gen HM moves (unless they also exist in 5th gen), refuse to transfer things like Spiky-Eared Pichu, and fix hex values. I would do it myself if I had the knowledge, but I unfortunately don't.