Is there an easier way to compare iOS to Android apps than manually checking each app?
Borrow an old iPhone and run the Apple migration tool by following the setup directions on iOS 9 or you could use the Relo tool to attempt a dry-run on the Android side.

That way, you can actually use the new OS for a bit and if it's unlocked, you could swap SIM cards between the two devices. If you don't mind the cash outlay, you could also buy a new phone outright and educate yourself on the return policy if you're mostly sure the change will be for good.