December 4th, 2017
I have seen a lot of people on Apple’s developer forums having problems running their apps on iOS devices running the latest version of iOS. If you find yourself in this situation, remember the following:
Xcode is unaware of future iOS versions.
What this means is if you’re running Xcode 8, connect an iPhone running iOS 11, and try to build and run your project on that iPhone, it won’t work. Xcode 8 shipped with iOS 10 so it doesn’t know about iOS 11.
This lack of awareness also applies to dot releases. If you’re running Xcode 9.1 and try to run a project on a device running iOS 11.2, it won’t work either because Xcode 9.1 shipped with iOS 11.1.
How do you fix this problem? You have two options.
Option 1 is easier because you don’t have to be constantly updating Xcode. But if you’re already running the latest version of iOS, Option 2 is your only option.