iOS allows you to delete ALL SMS messages from a person by sliding their name and pressing the red button that appears.
Thanks Apple. I wasn't trying to delete anything but accidentally slid the finger for whatever reason, saw a flash of the red button and bang, 4 or more years of SMS messages gone. Goodness knows how many, probably more than 4,000.
You'd think the iPhone would say "are you sure you want to delete five years and 4,000 messages?" yes/no?
Yes theres a backup from a few months ago somewhere. The messages aren't critical but it sure is annoying.