Tercel iTool
Developed to give customers easy access to information, the Tercel iTool is invaluable. It provides hydraulic calculation for bits in both international standard units and imperial units; it calculates TFA, pressure drop, jet velocity, internal nozzle size and HHP created at a nozzle orifice during drilling operations. The app also features interactive guides to the IADC Classification and Dull Grading systems for fixed cutter bits. The app is available through iTunes.

Download here:
http://itunes.apple.com/us/app/tercel-itool/id430414651