Does UIAutomation work for testing on the iPhone devices and can I do it without the xCode for the project?
Is there another tool that can test without the xCode?
Yes you can do UIAutomation for iPhone device with certain constraints. A new tool in iPhone know as Instruments which is now more powerful for testing.
For a good walkthrough go through the link http://mobileorchard.com/find-iphone-memory-leaks-a-leaks-tool-tutorial/