that's not how percentages work. If Apple takes a 30% cut of your price, then you have to raise your price by 42.8% to still make the same amount of money.
Ah, but if you offered the same service to Android users you couldn't do that, because you aren't allowed to price things differently between iOS and other purchasing options. Unless that has changed.
I believe there's no restriction on pricing on different platforms. If mostly wealthy people have iOS devices, then I might set app price to a higher value than Android just to encourage purchases on Android. I think no one will ever care.