It seems to me like you are expecting people to buy this app so that they can see what a color blind person would see with sample images. But who cares? You see

It seems to me like you are expecting people to buy this app so that they can see what a color blind person would see with sample images. But who cares? You seem to have identified that parents or relatives of colorblind would be one likely demographic. Although it is big but paying for it would be a hard for them to justify when they can show these examples on the web. If you could make an app that would show how an iPhone would look for color blind people I can quite a few people buying it. My point is that using this technology that you have you should expand on it.