Terminal message when running projects from book


I have just started going through the iOS programming 2nd edition, and am using the downloaded Window Based Application template,
but I have noticed a message in the Terminal / Log window that appears every time I run book project from the simulator.

Quiz[908:f803] Applications are expected to have a root view controller at the end of application launch

The above message does not stop the projects compiling, and running as expected, so there is no issues with the code, but I was wondering
if someone could tell me what the message means.

Many thanks.

Regards Mark


its a new warning message that was put in after this book was published. its not important.

You can search this forum for the answer. your not the first person to ask it.