[on_and_off]

Play Services comes bundled with Android terminals (at least, as long as they come with the Play Store) and among other things, it monitors apps for bad behavior and check the apps you want to install. Mobile OSes come with a very lock down model, so it is harder for an app to monitor other ones (except for Play Services with its specific privileges), so it is probably way harder to create an AntiVirus app that actually does something useful. As long as you don't install random apks (auto downloaded on shady websites or pirated apps), the chances of encountering an harmful app are very slim.