As a printer and designer and love the trade of print from letterpress to digital in 27 years and the colour changes that pantone have produced. I have found this little app to be of use showing to customers, but you have to have the knowledge of how colour changes with rgb, cmyk, and explain. I must say if you are a designer you must have the Colour Bridge euro book (used to be solid to process book) to actually show the difference in colour of the final finished product.