How can you migrate your project…

When you open a Swift 2.2 project in Xcode 8 for the first time, you are given the option to migrate your project to either Swift 2.3 or Swift 3 in order to take advantage of the new SDKs. However, if for some you decide that now is not the right time to convert, you can always do so later. The Swift Migrator tool is accessible in Xcode 8 under the Edit | Convert | To Current Swift Syntax… menu.

You will need to convert your code if you want to use the new SDK's available for iOS 10, macOS 10.12, watchOS 3, or tvOS 10. You have two options for migrating your project listed below:

Option1 - Migrating to Swift 3

If you want to build against the latest Swift and use all of the new features of Xcode 8, then choose the migrate to Swift 3 option. The Migrator will modify your source files to adhere to the new Swift 3 syntax.

Option 2 - Migrating to Swift 2.3

If you just want to use the new SDKs and aren't ready or able to migrate to the latest version of Swift, then...