The Apple Store, so far as I know, has some built in unsustainability because it supports update paths but doesn't have a way to charge for that service. In the long run, it will need either a new revenue source or a "trust" created by initial sales. In-app purchases probably provide this revenue source.
I think the end-game here is for Apple to create an "alternative minimum price" for apps that are free or already sold based on Apple's cost and a margin on the App Store generally. In-app purchase cuts will be charged until the total AMP has been reached.
That's probably a long way off, though. First Apple has to abandon an admittedly intuitive charging system. Second, there will probably need to be a point where the best apps are on Android and the App Store is bringing up the rear.
I think the end-game here is for Apple to create an "alternative minimum price" for apps that are free or already sold based on Apple's cost and a margin on the App Store generally. In-app purchase cuts will be charged until the total AMP has been reached.
That's probably a long way off, though. First Apple has to abandon an admittedly intuitive charging system. Second, there will probably need to be a point where the best apps are on Android and the App Store is bringing up the rear.