Question

import <Foundation/Foundation.h>

import"BMKAnnotation.h"

@interface BMKShape : NSObject <BMKAnnotation> {
@package
    NSString *_title;
    NSString *_subtitle;
}

I don’t convert the @package to .NET code!

Answer 1

Apple ObjectiveC documentation about @package states:

@package is a new instance variable protection class, like @public and @protected.
@package instance variables behave as follows:

    @public in 32-bit;

    @public in 64-bit, inside the framework that defined the class;

    @private in 64-bit, outside the framework that defined the class.

In .NET world that’s public visibility in 32bits and internal visibility in 64bits.
Since iOS is 32bits you should bind those as @public fields (or not bind them at all since they are likely something that is not meant to be used outside of the provided package).