Swift 2.0 and arm64 integration issue

[dinuvld]

I am trying to integrate FastPdfKit with my iOS Swift 2.0 app, but when I try to run it on my device (iPhone 6) it gives the following error:

Undefined symbols for architecture arm64:
"OBJC_CLASS$_ReaderViewController", referenced from:
OBJC_CLASS$__TtC9SmartRead7pdfView in PDFView.o
"OBJC_METACLASS$_ReaderViewController", referenced from:
OBJC_METACLASS$__TtC9SmartRead7pdfView in PDFView.o
ld: symbol(s) not found for architecture arm64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

This is really strange, since the app is running just fine in the simulator. Do you have any idea what could cause this problem?