Why Developers Create Apps for iOS
Marco Arment:
The problem is that hardware manufacturers and tech journalists assume that the hardware just needs to exist, and developers will flock to it because it’s possible to write software for it. But that’s not why we’re making iPhone and iPad software, yet those are the basis for the theory.
We’re making iPhone software primarily for three reasons:
Dogfooding: We use iPhones ourselves.
Installed base: A ton of other people already have iPhones.
Profitability: There’s potentially a lot of money in iPhone apps.
With this in mind, think about the installed based of Macs.