I just downloaded this very nice keyboard tool. It’s NOT just a chord finder. It’s only $2.99 in the App Store.
Octavian, Keyboard Calculator, is the essential musical reference tool for any musician, student, composer, songwriter, pianist, keyboard player, or hobbyist. Whether your specialty is classical, jazz, blues, or rock, Octavian provides instant access to over 500 scales and 50 chords, with any root note and in any mode or inversion.
Visit their website to find out more and watch video – http://www.bitnotic.com/octavian.html