Bluebox Security Scanner is a free app that will scan your Android device to see if your system is vulnerable to any of the master key security risks. It will also check to see if your system settings let "untrusted sources" install apps. And it will check to see if installed apps are trying to use any master key security flaws.
Download and Install Bluebox Security Scanner for Android
Here's how you can install BlueBox Security Scanner to protect your Android device.
1. Go to the Google Play page.
2. Tap the Install button.