How can I dynamically detect whether my application is system or normal?

Question

How do I differentiate between a system app and a normal app ? I looked through android PackageManager and could not find any.

Edit: I want

Answer 1

I see a comprehensive answer by Pankaj Kumar in this SO link : "How do I check if an app is a non-system app in Android?" OR in this blog by him : "http://pankajchunchun.wordpress.com/2014/07/08/how-to-check-if-application-is-system-app-or-not-by-signed-signature/" .