Read this: Hunting also has a significant financial impact in the United States, with many companies specialising in hunting equipment or speciality tourism. Many different technologies have been created to assist hunters, even including iPhone applications. Today's hunters come from a broad range of economic, social, and cultural backgrounds. In 2001, over thirteen million hunters averaged eighteen days hunting, and spent over $20.5 billion on their sport.[citation needed] In the US, proceeds from hunting licenses contribute to state game management programs, including preservation of wildlife habitat.

What has been developed in the U.S. to help hunters?
What is the answer? (If it cannot be answered, return "unanswerable")
different technologies