You're conflating the phones themselves with the secondary markets they create.
The problem is that Apple has a monopoly in selling/distributing Apps to iphone users. This is not the case on other operating systems, technically not even on android(eg. Samsung) and has nothing to do with a "monopoly on their own products".
The problem is that Apple has a monopoly in selling/distributing Apps to iphone users. This is not the case on other operating systems, technically not even on android(eg. Samsung) and has nothing to do with a "monopoly on their own products".