It is the first time I am going to sumbmit my app. I know from a document that launch images should be specified, but I have created my own launch view (a viewcontroller wit
Yes. It is required. http://developer.apple.com/library/ios/#documentation/userexperience/conceptual/mobilehig/IconsImages/IconsImages.html
Also it is the most easy task in the world. You just need to set an image as splash/launch image.
UPDATED : From Apple HIG : Design a launch image that is identical to the first screen of the app. The launch image gives users the impression that your app is fast and responsive because it appears instantly and is quickly replaced by the first screen of your app.
Updated link: https://developer.apple.com/library/ios/documentation/UserExperience/Conceptual/MobileHIG/LaunchImages.html#//apple_ref/doc/uid/TP40006556-CH22-SW1