Apple April 2018 will force all Apps to be built with iOS 11.
Beginning in April 2018 all new iOS apps submitted to the App Store must be built with the iOS 11 SDK. This is the method Apple uses to force developers to fall into line otherwise your app will not be in the store.
For the average developer using either Rad Studio or Visual Studio they will have to hope their IDE’s can be used and sent to the store. There could be issues with the IDEs that Apple tends to wait until a few weeks prior to releasing the final version. This alone may break the development cycle with your IDE.
iOS 11 has brought innovative features and the redesigned App Store to hundreds of millions of customers around the world. Your apps can deliver more intelligent, unified, and immersive experiences with Core ML, ARKit, new camera APIs, new SiriKit domains, Apple Music integration, drag and drop for iPad, and more.
Starting April 2018, all new iOS apps submitted to the App Store must be built with the iOS 11 SDK, included in Xcode 9 or later. All new apps for iPhone, including universal apps, must support the Super Retina display of iPhone X.
You can visit the Apple Developer web site to learn more about the iOS 11 SDK and XCODE 9