Was reading this book called "Test iOS Apps with UI Automation" by Jonathan Penn and I have my first trial of "UI Automation" inside Instrument today and it was quite interesting.
However I found there's some limitations when using UI Automation with my latest game.
Although it did pick up "most" of the actions I performed on the device: such as tap on a button, swipe up or left, ...etc, occasionally it will miss a few swipe actions - and this makes it quite annoying. As my game relies heavily on user interaction, the execution of the test script failed quite frequently - as if user didn't swipe properly, the following action to tap on an button will certainly fail! I then have to track down which line failed, and manually add the swipe action.
Probably for iOS applications that has fixed buttons/tables would have a much higher success rate with UI Automation. Still recommend everyone to have a play with it, as it might save you lots of time with testing!