[chongli]

The issue with the App Store model is that it's just another platform to market yourself on. In your case, you benefitted from a first-mover (or early-mover) advantage and did well. Over time the App Store becomes more and more saturated with apps and so the value to developers goes down. This is no different from the web! It's merely offset by a few decades.

If you had put up your website back in the early 90's and were judicious about advertising back then, you might've been a Fortune 500 company (depending on your business niche, of course)!