Xcode9 cannot read swift2. Xcode 8.2 cannot run on ios10.3. Now what?

Question

So, today I updated the ios on my iphone to ios10.3. Then I clicked to run my project in xcode, and... xcode8.2 responded that it does not support devices running ios greater than 10.2, and that I should update xcode. So then I updated xcode to the current version which is xcode9.0. So then Xcode says that it cannot read swift2.3 projects, and that I must use a lower version to convert to swift3. Now I read here on stackoverflow that only xcode 8.2 is able to convert my project to swift 3. But then if I do so, my project won't compile on my phone. What am I supposed to do?

What to say about old projects I have around? Why would Apple make Xcode stupid that it cannot read any version of swift?! How am I supposed to convert and compile any old projects now and in the future?

Answer 1

Update Xcode 8.2 to 8.3 to support iOS 10.3. Use Xcode 8.3 to update your Swift 2 code to Swift 3. Then use Xcode 9 to migrate to Swift 4.

You can find different versions of Xcode at https://developer.apple.com/download/more/

Apple is always moving forward. If you wish to be an iOS/macOS developer you need to keep up.