I\'m trying to submit my first app in iOS. I have entered iOS Provisioning Portal and I am about to create an app ID. 
Lets say that I name
I know that its late but it might be helpful for people who need to change the Bundle Identifier of the app. In the finder go to the project folder:
the project file --> Right click on your project file '*.xcodeproj' 

--> choose 'Show Package Contents' 
--> Double click to open 'project.pbxproj' file 

--> find 'productName = NAME_YOU_WANT_TO_CHANGE' in the 
    '/* Begin PBXNativeTarget section */'
The ${PRODUCT_NAME:rfc1034identifier} variable will be replaced with the name you have entered and new Bundle Identifier will be updated to what you need it to be.