I would like to push a video into iPhone simulator to test video picking in UIImagePickerController. Is it possible to do that? And if it possible, could you please provide
You can subclass UIImagePickerController to override its behaviour and provide your own view. If you do this, you can then call imagePickerController:didFinishPickingMediaWithInfo: and supply your own pre-recorded video. If you include a video actually recorded from an iPhone 3GS, the behaviour you get will be pretty damn similar to that of the actual device.
Of course, always always always test on a real device before shipping!
We use a subclass of CLLocationManager in a very similar fashion to give a better location simulation.