You can do this without iTunes and even if the file is somewhere else in the sandbox other than Documents.
Go to Window/Devices in Xcode.
Next, select your device, and find the app in the list.
Now, look at the little gear icon at the bottom of the devices window. Click that bad boy.
See "Download Container..." in the list. Guess what that does? You got it. It downloads the whole sandbox with all the folders in the app's sandbox. Right click and "Show Package Contents".
This should let you see the sandbox of apps that have not yet been released. So, good for testing on a real device.
If you're testing on a simulator life is way easier. Just download the free app OpenSim here . Update: These days I prefer SimSim, also free here.
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