In a notice sent out to iOS developers today, Apple is reminding everyone how important it is to adopt the 'iOS7' look and feel with a soft warning about any new or updated apps being submitted to the app store.
From Apple
'Make sure your apps work seamlessly with the innovative technologies in iOS 7. Starting February 1, new apps and app updates submitted to the App Store must be built with Xcode 5 and iOS 7 SDK'
Don't worry Corona, Gamesalad, Unity, and other developers. When they say 'must be built using xCode5' they are meaning the compiled version of the app which most 3rd party libraries are now using when creating your .app files written in a language such as LUA. If the warning said anything about 'only using objective C' we'd hear mass cries from just about 80% of the developer community!
What this essentially means is you can't target older devices any a longer with your apps, and it further goes to almost completely bury any iPhone, iPod, or iPad that can't run iOS 7.