Why do you need anti virus for s4? Sorry i dont use one for iphone. Please explain. Thanks
You'll get a variety of conflicting answers to this question every time you ask it.
Personally, I feel that common sense and safe practices are the #1 defense against malware, and no anti-virus or security software is going to ever provide 100% flawless protection (because they'll always be at least 1 step behind those writing the malicious code). I'd actually love to see a survey of all those who run AV on their phones who have actually ever averted an incident because of them (seriously, I'm not trolling or saying it doesn't happen, I'm honestly curious as to how often, if ever, it does).
The fact is that if you only install apps from the Play Store from known, trusted developers, then your risk of getting malware on your device is pretty slim. If you want the warm, fuzzy feeling that running security software can provide, then by all means do it.
I work in IT, and I can't tell you how often friends and family will bring me computers that are laden with viruses and malware asking me, "why is my computer so slow and full of popups!!!". When I explain to them that it's full of viruses, they say, "how'd I get a virus?!? I have anti-virus software!!!". Fact is that even with most up-to-date AV, often the only thing security software is good for is telling you that you already have problem. Am I saying nobody should install anti-virus on their computer? No, absolutely not. Am I saying that you should always use safe practices and common sense when doing anything online and not trust AV to act as an infallible protective shield? Yes.