Well, I tried it... The free version has a too-limited range of stones and cuts TBH; you can get a feel for the interface, but I can't see any practical use for the app in that form. Including characteristics of the stone in question is nice. I'm not sure about the intended price for the full app; on the one hand, it's a limited market but on the other hand that's a lot for a fairly simple smartphone app (speaking as a software engineer).
Perhaps it's time I wrote a useful app for jewellers. Mostly I suspect it would end up as a collection of task-specific calculators...
Scrapping iPhones?Maybe they could use a similar technology for scrapping?
there's gold in them thar iPhones!