Quote: "Xcode = Obj C & C++ only"
That's true if you use Xcode as a compiler.
You can use Xcode with Free Pascal however. In that case, Xcode will run the Free Pascal compiler (through a script) and than perform the additional packaging and code signing. That is how you use AppGameKit for Pascal to create iOS applications.
If you want to look at some details, then open up one of the AppGameKit for Pascal samples in Xcode (there is an Xcode project for each sample). This is what is different from ObjC/C++ projects: Under "Build Settings" there is a group with "User-Defined" properties. You will find all the compiler options here that are passed to the Free Pascal compiler. Also, under "Build Phases" there is a "Run Script" section that runs the Free Pascal compiler using the specified compiler options. This is a standard script and you don't really have to worry about how it works.
Even though Xcode does not natively understand Free Pascal, you can still use it for debugging. For example, you can place breakpoints in the Pascal code and then run inside Xcode. However, it is usually easier to debug with Lazarus.
See
this page for more info on using Free Pascal with Xcode.