iOS tutorial UIImage error

In the tutorial https://www.raywenderlich.com/1797/ios-tutorial-how-to-create-a-simple-iphone-app-part-1, I get an error on the RWTScaryBugDoc.h page that says “Property with ‘retain (or strong)’ attribute must be of object type” and “Unknown type name ‘UIImage’.”

Then on RWTScaryBugDoc.m, I get errors “Expected a type” and “Implicit conversion of an Objective-C pointer to ‘int *’ is disallowed with ARC.”

Any ideas on how to fix these?? Perhaps the errors are happening because there’s a new version of xcode from what’s described in the tutorial? Thanks!!