Why don't you already have this? – pCAM FILM + DIGITAL PRO Review

This app should be considered a mandatory tool for anyone involved in cinematography, just like a light meter. I can not think of an excuse to not have this on your $500 phone if you consider yourself a professional camera man. It is simple to use and the interface is straight forward. Yes it is worth it. High 5's to the developers.
Review by Glenn Derry on pCAM FILM + DIGITAL PRO.