I am living proof that it is still quite possible to make a solid and reliable income from the App Store. The way in which I have been able to do that, however, has been to change with the times and constantly adapt to the changes in the market.
David’s apps aren’t perfect, but what he doesn’t mention is that he’s a nice guy and very respectable online — I unfortunately haven’t met him in real life. I buy his apps because, while not perfect, they’re solid problem solvers and appeal to my needs. I know that the fact that he has an online presence makes a difference for me — he won’t disappear tomorrow and leave me looking for alternatives.
Good luck on another eight, David!