In last months on the App Stores (oops... hope Apple didn't mind I used that copyrighted/patented/reserved word!) the Antivirus apps for Android are proliferating.
Everyone wants it, just to install and then recognize it slow down so much his droid to make it far less usable than before. But droids really need antivirus?
Actually android virus are very few, cannot widespread as Windows ones, and cannot do much damage to your phone if you don't allow it, giving them superuser permissions on a rooted phone. Aside, if you're brave enough to root your phone, you should also be smart enough to manage that extra control you have over your droid installation, isn't it?
What you should care about instead are permissions for app you install. Every time you install an app, you get the list of the permissions this app will take. Let say you are installing a small game, and the permissions list asks for the game access the internet (ok, should be, if it is ad supported, or needs to downloads levels from the net), you call log (why???) and your phone ID (ok, that could be).
The big question here is why that game needs to access my calls log. There's no reason for that. But you absolutely want to play that game. So you need a way to limit the app permissions some way. And that's possible.
Instead of antiviruses, I found much more useful (and less intrusive) permissions control applications, such as LBE Privacy Guard. You can control and limit you apps permission, with a very small impact on battery and performances (almost none). Considering the great benefits of that, LBE is a must-have-app on every droid.
Obviously, you can run it only on a rooted phone. Otherwise, you really don't need permissions control - you just have to read carefully every time you install a new app.