Activity Object Reference MainActivity@3f62f3e7 is different after Back

Hi,

Would need some help to understand the Activity creation.

I have just an Example App with one Activity and one Fragment in it,
so when I logging the object reference id of the Activity in the onAttach method of the fragment I receive: "MainActivity@3f62f3e7".

My Problem is:

Even when I kill the App in the Task Manager of my Android and then I start the App I got the same object reference Id "MainActivity@3f62f3e7".

If I stop the App within the Backbutton then the reference is different e.g.MainActivity@17c7a065.

And after that, If I kill the app completely I get the old reference Id: "MainActivity@3f62f3e7".

so WTF?