iPhone - application displays a blank screen when loaded on a real device (sometimes)

I currently have an iPhone application that runs fine on the simulator and also runs fine on a real device when it is connected to the Mac and is attached to the Xcode debugger.

I can close the app and open it again no problem.

However when I remove the device from the mac usb and try to use my application normally it sometimes tries to load and gets stuck on a blank black screen. Other times it will load normally and if I press the home button and launch the app again it usually launches fine.

The device is setup for debugging and I simply place the app on it by running it on Xcode, so is this my problem? Do I need to change the apps settings to get it to run on the device without this issue to a release version or something along those lines?

EDIT:

I have some additional info that seems to reproduce it everytime.

It happens if I push my app to the background by pressing the home button, then I leave the device lying there for around 5 minutes and when I click on the icon to launch my app again I see my app 开发者_Python百科for a split second and then its a black screen