> They would not have sold as many millions of iPhones, iPods (heck, even Macbooks) in the last decade, if Instagram & Facebook weren't there to suck people in to their platform

I really don’t see the logic in this.

It’s pretty obvious these devices were useful for many things - messaging and the web would have been enough to guarantee growth.

I think you have the causality the wrong way round.

People only use Facebook so much because the iPhone put it in their pocket rather than on their desk.