Can you explain what you mean by "suspend"?
Im looking for a command which returns to the device homescreen/desktop and doesnt closes the app completly.
I want the behaviour like if u press the hardware home-Button. The app still runs in the background and if u restart the app its in the state before u pressed the home button. In contrast if i use the code line posted above the app is really closed and doesn't runs in the background any longer.