Anti-trust cases aren't decided on binary terms. It's the overall act that's illegal. In other words just because the situation with Apple is different from Microsoft's anti-trust case doesn't mean Apple could not be violating the law. Paying or accepting money for the purposes of a company receiving an unfair competitive advantage is also covered under anti-trust laws such as the Advanced Micro Devices, Inc. v. Intel Corp case.
https://en.wikipedia.org/wiki/Advanced_Micro_Devices,_Inc._v....