» Glossary » Killer application
A program that acts as a catalyst for the market of a bigger system that includes it.
VisiCalc was the first killer application. It was a spreadsheet program distributed with the Apple II that drove the computer sellings, opening the market for apps for personal computers beyond the games.
The same effect can be seen in other markets: in the video games arena there are games that are specifically designed to take advantage of the full capabilities of the console and drive the sales of the hardware; WhatsApp -to send free messages- was the killer application for high-end mobiles for the mainstream market.