lldb has a way to provide custom formatting for specific types. Look here for details:
http://lldb.llvm.org/varformats.html
The only restriction is that this facility maps types -> formatting options. So you can't do things like "If I see an int in some context, treat it as a float", you can only do so for ALL ints. But if you have a wrapper type that contains the ints in question, you could pretty easily write a formatter that reinterprets the contents of the wrapper type.
The LLDB API's will render values using the data formatters described above, as will all the command-line commands that present data. AppCode may use lldb's implementation of the gdb-MI interface, and I don't think that supports the data formatters. So you may or may not be able to see the results in their Locals view.