Andy Finnell: “The problem that you’re likely to have, like most developers, is setting a price that you can live on. The temptation will be to price your app too low, such that developing the application isn’t sustainable. You might have the best of intentions, but in the end you’ll cause the premature death of your business before it even gets a chance.” (Via Daring Fireball.)
I’ve watched the software world long enough to know that competing on quality is a good idea. Price your software high enough so you can keep afford to keep working on it — and make sure your software is the best you can make.