Security software firewall also. Firewalls can control what goes into the phone, as well as downloads. This eliminates most of the virus even before entering the phone, which is very handy.
Most mobile security programs do not use a lot of resources on your phone. Most times you can not even notice that you have a mobile security software in use. In addition, the battery does not have much impact if it does at all.
Most mobile security are very cheap. Norton Mobile Security is only $ 29.99 per year per phone, which is only 8 cents a day.
Mobile Security protects your phone very well. This is great because most smart phones today store a large amount of data, and some information can be invaluable. The mobile security software is easily worth the money, especially if you get a lot of data.