I have searched through all the documentation available on services,
and could not find anything related to this, and none of the examples
shed any light on this. After some further research and meddling with
my code I found that this does the trick inside my service:
Intent intent = new Intent(this, ExampleActivity.class);
intent.setAction("android.intent.action.MAIN");
intent.addCategory("android.intent.category.LAUNCHER");
PendingIntent contentIntent = PendingIntent.getActivity(this, 0,
intent, 0);
This will match the action and category set when launching the
application from the application list or desktop and therefore only
one instance is ever created.