Let me introduce for Android Smartpphone product from virus.

Avast is most popular of PC vaccine industry. As i also used before. Android based of Linux and user make own application. It means network port always open. Virus can into Android Phone anytime. So user can't make virus kill user self.  

 
Most important thinks and why need vaccine need to your smartphone. Please visit to manufacture site.
<http://www.avast.com/free-mobile-security#comparison > 

To run avast! Free Mobile Security your device must meet the following criteria.

Operating Systems Supported

• Android 2.1.x
• Android 2.2.x
• Android 2.3.x
• Android 3.x
• Android 4.x

Minimum Hardware Requirements

• Any phone capable of running a supported system
  
  
  Android market links
  <https://market.android.com/details?id=com.avast.android.mobilesecurity> 
  
  
  More information? As flowing link
  http://www.avast.com/free-mobile-security#comparison 
   
  Please protract of you phone from virus.