Then say market power instead of monopoly and no one will ever dispute that. Of course Apple can and does set the price of its products above their marginal cost. Doesn't have quite the ring to it as "monopoly" though.
This is such banal point to make when Apple combined with Google have Duoloply. With Apple's advantage in App store spending Apple basically dictates whatever they want to App developers. So saying that they have monopoly like powers is completely and entirely correct.
