I am developing an app that support iOS 4.0 or above. As iOs 4.0 can be installed in iPhone 3GS, iPhone 4, iPod touch 3rd gen, iPod touch 4th gen. The app will be run in non retina display device and retina display device.
I understand that the OS will determine which image file to display (2x resolution or normal resolution) depends on the devices. If I only have retina display device for testing, can I just use the simulator to test that the UI look good in non retina display?