I think it's likely a bit more complicated than a simple app as I don't think an iPhone or Android app by itself would have the bandwidth to do the processing that will likely be required (at least not if my suspicions are correct). I still think it's doable, but I think more than just an app will be required to get the desired functionality with today's technology. In other words, I don't think this is currently a candidate for an app incubator.
It's already been done called coin book pro
You cant grade with a cheap cellphone camera. It costs money to have a coin officially graded....
Well I had the idea submitted before. I wouldn't post it and let people steal it
It's not about can you make the app or not, it's if you can get the grading companies to agree to grade by photo only. and that I highly doubt. It's a great idea as a third-part grading service, but to get official grades seems unlikely. Still it'd be cool!