When Apple released the ‘Retina’ Macbook, they took away the capability to set the screen resolution to a specific resolution. (Rather, they now have ‘scaling’ with fluffy values like ‘Larger Text’ and ‘More Space’ rather than discrete values.) When I had to do a demo/presentation at a conference, I was suddenly unable to set the output resolution to the specific resolution that I needed for my demo (which at that time was 720p). I then stumbled onto this wonderful utility, and suddenly I have EVEN MORE control over output resolutions than ever before. This utility was a life saver - and at such a cheap price, it is truly incredible value.