to attack it. Although, Android is supposed to be safer than iOS for any malicious attacks, the opposite of the computer world where OS X is far more immune than Windows. I also run a custom ROM since I rooted my phone, I don't know if that makes my any safer or not but it does get rid of all the bloatware.
There is also Lookout that's supposed to be good.
If you do run one, get one that has a remote finder/locker whatever they call it. Then if your phone is lost or stolen you can control it via a friend's phone or the web and track it and delete everything or lock it or make it make a loud sound. I say that but I haven't set mine up for that since avast! implemented web control.
You can also get apps that will check the permissions of all the apps you have on your phone so if you install a lot of apps it will tell you which ones access your network or contacts etc... then you can block them if you get Droid Wall. I've gotten so lax with my phone lately... I don't remember which permission checker I use or if I put it back on after the last time I wiped and flashed a ROM. Otoh, I tend to not install apps that aren't well known that have too many permissions.
There's some forums about Android phones that have tons (much more than you'll need) of info. You can read general forums or find the one specific to your phone.
http://forum.xda-developers.com/
http://androidforums.com/
http://forums.androidcentral.com/
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