Depends on your threat profile doesn't it. I run iOS and have considered for me, I don't need anything more. But if you were a potential target of someone who had motives, then perhaps AV on Android is a good idea, perhaps an even better idea is move to iOS*.
* This isn't a "this OS is better than your OS", there are many ways that Android is better than iOS - just not for security.
* This isn't a "this OS is better than your OS", there are many ways that Android is better than iOS - just not for security.
