Is it possible to know when application starts in windows phone 7?

Question

I want to know is there any mechanism by which my C# code knows that application starts. For example when camera or music player starts then my app know each time that camera or other app has started.

Answer 1

No, you cannot listen for when other applications start. You can use Launchers and Choosers to start the Camera from inside your own application, but you cannot listen on other applications.

Anyway, such a application would also be considered spyware.