I haven't used Android, but culturally it seems like iOS developers try to deliver as much as they can with the permissions you give them. A voice recording app would probably just refuse to function without microphone access, but a video app will typically simply record a silent video if you give camera access but deny microphone access.

I don't know if this is enforced by Apple's review process or whether it's an emergent custom.

Snapchat records silent videos if you disable microphone access, but disallows access to the entire app if you disable camera function.

You cannot even read other people's snaps without enabling camera. I deleted the app because of this function.