Have you noticed in iPhone Mail App that while you are typing an email address of a person it sometimes autofill’s the email which might be cool at times but not that good when that email is not valid or intended to be sent to. This App for iPhone Provides a Way for user to Clean up the email autofill entry list, where user might accidentally entered the wrong email address when he/she composes a mail, or the email address simply becomes obsolete. This Helps the User not to see any irrelevant email addressess from autofil when he/she composes an email.
You can download this Tweak from Cydia for JailBroken iPhones. You can simple goto the App setting an remove unwanted email addresses that comes up automatically while you type an email while composing.