The AppCode IDE home page states that:
AppCode natively supports Objective-C, Swift, C and C++, including C++11, libc++ and Boost, as well as JavaScript, XML, HTML, CSS and XPath. Use your preferred language to create your iOS/OS X application.
The CLion IDE is also meant for C and C++ but AppCode handles more languages.
Does AppCode implement all the functionality of CLion?
A yes answer I would think means it is better to go with AppCode. An explanation against this is appreciated if you disagree.
Note: I have not yet used AppCode.