How can I resolve this type of error, when running an app for IOS in xcode 9.
How can I resolve this type of error, when running an app for IOS in xcode 9.
Update your xcode, the error is that this framework was compiled with swift 4 while you are trying to compile with swift 3, just update the xcode ... or look for the equivalent to that framework for your version of swift.
Your framework called Crypto ( Crypto.framework ) is currently compiled with Swift 3, and you are using Swift 4 (it seems).
It would be very helpful if you would share your Cartfile to see which library Crypto you are using, since I have seen several options and I do not know which one you are using:
Review the documentation and confirm that your library is supporting Swift 4.