Android or iOs?

Over time, I've heard people argue endlessly over this same topic, but today, I'd like "actual users" to bare their minds on this.

Personally, I'm an android user and I'll go for android over ios (probably cos I've never used an ios based device before).

But I know many of you have had the opportunity of experiencing both worlds.

Now the question is: ios or Android? Which do you prefer and why?

Is it the battery life?
Camera?
Fluency in performance?
Sleekness?
Security?

Do tell!
Elaborate fully so next time when someone goes out there to get a new device, he or she wouldn't be torn between an ios based device and Android!