With my iPhone connected to my mac via 30-pin connector (standard apple/iphone cable) I of course test and run my app with Xcode building it to run on the device.
For some reason though, when I build and run, it installs on my device but doesn't go further than the loading screen of the app with Default.png showing.
Then if I stop the build in Xcode it quit the application, then I run in manually on my device and the new build is there for me to test, but I just don't know why I have to do that and it doesn't just run past the loading screen when building?
This happened to me once after I added some certificates. I removed the build directory (MyApp/build/) and then did a clean and then build again, and everything miraculously worked. You might try that.