问题 When you install an apk file that is from an unknown source, Android will complain and verify that you want to install that apk file. This file must be checked to a list of known sources. I am interested to know where that list of known sources is located on Android AOSP. Edit: I apologize if my question is confusing but allow me to clarify. When you install an APK from usb or email Android will prompt you saying you are installing an app from an unknown source. At this point you can either