This IOS: launch image multiple language dates back to 2012.
It is a procedure that works well when running the app both on simulator and devices.
However, it fails itunesconnect
validation after submit (invalid binary).
Your binary is not optimized for iPhone 5 - - New iPhone apps and app updates submitted must support the 4-inch display on iPhone 5 and must include a launch image referenced in the Info.plist under UILaunchImages with a UILaunchImageSize value set to {320, 568}. Launch images must be PNG files and located at the top-level of your bundle, or provided within each .lproj folder if you localize your launch images.
Also see "Your binary is not optimized for iPhone 5" after I upload an app with xcode 6.0.1
So despite it's possible to localize spalshscreen on development, is it possible to do it for real?