I think you mean 0.7% of people, which is not necessarily a small market. Developing a sophisticated consumer electronics product like the iphone may be expensi

I think you mean 0.7% of people, which is not necessarily a small market. Developing a sophisticated consumer electronics product like the iphone may be expensive, but developing a few software apps for it isn't necessarily, especially if you can dominate the market for the accessible phone. That said, I would agree that there are more compelling markets out there. I wouldn't be surprised if most accessibility developers have altruistic motives.