Does the iPhone require an antivirus?

Just wondering if iPhones need an antivirus or firewall?

Yes 

 

iPhone Has an app let me show you.

 

Lookout mobile security Free

yes but only Apple would create it

additional question:
Does Iphone use like adobe flash player and adobe reader?
If so, does one need to update those like one would do on a desktop pc?

Just wondering if iPhones need an antivirus or firewall?