what is "Killer Application"?

Answer
A "killer application" or "killer app" is a software application that is exceptionally useful or exciting, often representing the first of a new breed and being extremely successful. It is innovative and can drive sales and growth of the overall platform or company, providing a major source of competitive advantage, brand loyalty, and profitability. The term "killer app" is commonly used in marketing to describe a computer program that is so necessary or desirable that it proves the core value of some larger technology, such as computer hardware, a gaming console, software, a programming language, a software platform, or an operating system. In other words, consumers would buy the hardware just to run that application. The concept of a killer app has been around for decades, with examples such as the VisiCalc spreadsheet for the Apple II in the late 1970s, Lotus 1-2-3 and Excel for the IBM PC in the 1980s, and the Mosaic Web browser for the Internet in the early 1990s. These applications were so good that they provided reason enough to purchase the hardware, becoming the defining feature of their respective platforms. In recent years, the concept of a killer app has been applied to emerging technologies such as artificial intelligence (AI) and virtual reality (VR). For example, the Apple Vision Pro, a VR headset, already has over 1,000 native apps, which could be considered a "killer app" for the device. However, the idea of a single app driving new hardware adoption has been questioned, with some arguing that hardware, developer ecosystem, and overall utility are just as important as the app itself. In summary, a killer application is a software application that is so useful or distinctive that it proves the core value of some larger technology and drives sales and growth of the overall platform or company. It can be a major source of competitive advantage, brand loyalty, and profitability, and has been a defining feature of many successful technologies throughout history.
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