Apple has no monopoly in any market. Their platform terms and conditions may (or may not) be draconian, but what antitrust concerns can be taken seriously? Apple owns a small (but profitable) share of every market in which they operate.
Antitrust "monopolies" aren't monopolies in the sense of no other players, they are monopolies in the sense of practical lack of competitive pressure displayed through market power (also known as pricing power) which is the ability, within some -- potentially narrow -- range to raise prices without losing sales to competitors (hence "pricing power", but market power could perhaps also be demonstrated by being able to make other adverse changes without driving sales from the party with market power to competitors.)
In a sense, this does match the "no competition" definition, in that having market power indicates that while there may be other players -- or even bigger players -- in a named market, they aren't in a practical sesne actually acting as competitors in the sense of economic theory, because the goods are revealed by market behavior not to be substitutes.
I agree that they're unlikely to be spanked under antitrust rules--unless they end up dominating the smart watch market, in which case they'll be very vulnerable, but they're not there yet. But even if they don't fall under those rules, they're definitely under scrutiny.
Plus, Apple is definitely heading where Microsoft was: perceived as big enough to be the public's favorite piñata. That may ultimately be a bigger problem for them than any business realities.
