This simply isn't true, the market is too diverse to make any assumption like you just did. Some do upgrade based on "hardware specs." Go ask your mom what mhz are. Yea, I'll wait.

iOS is the large reason people choose iPhones over Android. The phone is simply a portal to iOS.

Without the OS the phone is essentially a brick. To argue the hardware is the only product is an absolute falsehood.

I agree with you that iOS is the product, but I agree with the GP that the capital-letters App Store has very little to do with it.

To re-use your mom as the argument:

* Go grab her phone and point at any given app, and ask if it's available on Android too.

* Ask her if she knows the differences are between the Play Store and the App Store.

* Ask her if she thinks there is any material difference between getting applications onto an Android phone versus an iPhone.

She presumably doesn't know anything about these things, makes the assumption that apps are apps, and leaves it at that.

The App Store didn't exist before iOS, it was created for it. It is not a separate product.

None of these questions get you anywhere. You made the claim that hardware was why people upgraded - which is false because of the diversity of the market and the fact that the hardware is only a portal to what they want. You haven't dealt with the argument - that the App Store is a separate product from an iPhone. It isn't.