I’ve never even thought about it like this @rune
I’ve always just used the same app for both Android and iOS.
The advantage that I can see with having 2 separate apps would be for app updates in the app stores, where you can manage specific sets of features catered to each platform individually. For example, you can style screens like iOS themes and/or android screens for a somewhat ‘seamless’ experience for the user on their specific device. Like iOS notification modal screens.
The disadvantage would be double the work when adding new features or modifying existing ones when both apps have the same things.