Two iPad App's Cymbol is better, iEmoji emoticon alternate is out there
Not true!
Some basic emoticon iEmoji iPad App's will do a true copyright ©, as a single character entry.
Cymbol on iPad is out there, reviews are there indicate it is more powerful as an editor.
http://idevicesworld.com/features/cymbol
http://ipadcto.com/2012/03/22/pilcrow-dagger-and-copyright-a-writers-symbols-characters-and-scripts/
Okay, iPad does support superscripts and subscripts, plus other items via that Cymbol App in the App Store.
Spread the word to help end the frustration of other writers!
Also, you can type in other special characters with the hex to Unicode conversion, giving access to thousands or other symbols and foreign language sets.
So just Google for the hexadecimal and highlight inside of the snippet editor environment of Cymbol App with copy all button, paste into your other editor or iWork App, Keynote, Numbers or Pages.
Note, the Apple Volume Purchase Program for buying iPad App's includes this one too. So as a companion for Keynote, Numbers and Pages, it is a logical combination.