“It also looks for behaviors that indicate an application might be misbehaving, and compares it against previously analyzed apps to detect possible red flags. We actually run every application on Google’s cloud infrastructure and simulate how it will run on an Android device to look for hidden, malicious behavior.
Sandboxing: The Android platform uses a technique called “sandboxing” to put virtual walls between applications and other software on the device. So, if you download a malicious application, it can’t access data on other parts of your phone and its potential harm is drastically limited.
Permissions: Android provides a permission system to help you understand the capabilities of the apps you install, and manage your own preferences. That way, if you see a game unnecessarily requests permission to send SMS, for example, you don’t need to install it.”