# Killer application

A killer application (often shortened to killer app) is any software that is so necessary or desirable that it proves the core value of some larger technology, such as its host computer hardware, video game console, software platform, or operating system. Consumers would buy the host platform just to access that application, possibly substantially increasing sales of its host platform.

## Examples

Although the term was coined in the late 1980s one of the first retroactively recognized examples of a killer application is the VisiCalc spreadsheet, released in 1979 for the Apple II. Because it was not released for other computers for 12 months, people spent US$100 (equivalent to $400 in 2024) for the software first, then $2,000 to $10,000 (equivalent to $9,000 to $43,000) on the requisite Apple II. BYTE wrote in 1980, "VisiCalc is the first program available on a microcomputer that has been responsible for sales of entire systems", and Creative Computing's VisiCalc review is subtitled "reason enough for owning a computer". Others also chose to develop software, such as EasyWriter, for the Apple II first because of its higher sales, helping Apple defeat rivals Commodore International and Tandy Corporation.
The co-creator of WordStar, Seymour Rubinstein, argued that the honor of the first killer app should go to that popular word processor, given that it came out a year before VisiCalc and that it gave a reason for people to buy a computer. However, whereas WordStar could be considered an incremental improvement (albeit a large one) over smart typewriters like the IBM Electronic Selectric Composer, VisiCalc, with its ability to instantly recalculate rows and columns, introduced an entirely new paradigm and capability.
Although released four years after VisiCalc, Lotus 1-2-3 also benefited sales of the IBM PC. Noting that computer purchasers did not want PC compatibility as much as compatibility with certain PC software, InfoWorld suggested "let's tell it like it is. Let's not say 'PC compatible', or even 'MS-DOS compatible'. Instead, let's say '1-2-3 compatible'."
The UNIX Operating System became a killer application for the DEC PDP-11 and VAX-11 minicomputers during roughly 1975–1985. Many of the PDP-11 and VAX-11 processors never ran DEC's operating systems (RSTS or VAX/VMS), but instead, they ran UNIX, which was first licensed in 1975. To get a virtual-memory UNIX (BSD 3.0), requires a VAX-11 computer. Many universities wanted a general-purpose timesharing system that would meet the needs of students and researchers. Early versions of UNIX included free compilers for C, Fortran, and Pascal, at a time when offering even one free compiler was unprecedented. From its inception, UNIX drives high-quality typesetting equipment and later PostScript printers using the nroff/troff typesetting language, and this was also unprecedented. UNIX is the first operating system offered in source-license form (a university license cost only $10,000, less than a PDP-11), allowing it to run on an unlimited number of machines, and allowing the machines to interface to any type of hardware because the UNIX I/O system is extensible.

## Usage

   One mark of a good computer is the appearance of a piece of software specifically written for that machine that does something that, for a while at least, can only be done on that machine.
The earliest recorded use of the term in print is in the May 24, 1988 issue of PC Week: "Everybody has only one killer application. The secretary has a word processor. The manager has a spreadsheet."
The definition of "killer app" came up during the deposition of Bill Gates in the United States v. Microsoft Corp. antitrust case. He had written an email in which he described Internet Explorer as a killer app. In the questioning, he said that the term meant "a popular application," and did not connote an application that would fuel sales of a larger product or one that would supplant its competition, as the Microsoft Computer Dictionary defined it.
Introducing the iPhone in 2007, Steve Jobs said that "the killer app is making calls". Reviewing the iPhone's first decade, David Pierce for Wired wrote that although Jobs prioritized a good experience making calls in the phone's development, other features of the phone soon became more important, such as its data connectivity and ability to install third-party software (which was added later).
The World Wide Web (through the web browsers Mosaic and Netscape Navigator) is the killer app that popularized the Internet, as is the music sharing program Napster.

### Applications and operating systems

* 1979: Apple II: VisiCalc (first spreadsheet program and killer app)
* 1979: TRS-80, CP/M systems: WordStar 1982: ported to CP/M-86 and IBM PC compatible/MS-DOS
* 1983: IBM PC compatible/MS-DOS: Lotus 1-2-3 (spreadsheet)
* 1985: Macintosh: Aldus (now Adobe) PageMaker (first desktop publishing program)
* 1985: AmigaOS: Deluxe Paint, Video Toaster, Prevue Guide
* 1993: Acorn Archimedes: Sibelius
* 1995: Windows 95

### Video games

The term applies to video games that persuade consumers to buy a particular video game console or accessory, by virtue of platform exclusivity. Such a game is also called a "system seller".
* Space Invaders, originally released for arcades in 1978, became a killer app when it was ported to the Atari VCS console in 1980, quadrupling sales of the three-year-old console.
* Star Raiders, released in 1980, was the first killer app computer game. BYTE named it the single most important reason for sales of Atari 400 and 800 computers. Another was Eastern Front (1941), released in 1981.
* Dungeon Master, released for the Atari ST
* Defender of the Crown, released in 1986 for the Amiga as the first game from Cinemaware, has graphics which "have set new standards for computer game".
* In 1996, Computer Gaming World wrote that Wizardry: Proving Grounds of the Mad Overlord (1981) "sent AD&D fans scrambling to buy Apple IIs".
* The Famicom home port of Xevious is considered the console's first killer app, which caused system sales to jump by nearly 2 million units.
* Computer Gaming World stated that The Legend of Zelda on the Nintendo Entertainment System, Phantasy Star II on the Sega Genesis, and Far East of Eden for the NEC TurboGrafx-16 were killer apps for their consoles.
* The Super Mario, Final Fantasy, and Dragon Quest series were killer apps for Nintendo's Famicom and Super Famicom consoles in Japan.
* John Madden Football's popularity in 1990 helped the Genesis gain market share against the Super NES in North America.
** Sonic the Hedgehog, released in 1991, was hailed as a killer app as it revived sales of the three-year-old Genesis.
** Mortal Kombat helped pushed the sales of the Genesis due to being uncensored unlike the Nintendo version.
** Streets of Rage became a system seller for the Mega Drive/Genesis in the UK.
* Street Fighter II, originally released for arcades in 1991, became a system-seller for the Super NES when it was ported to the platform in 1992.
** Donkey Kong Country for the SNES helped Nintendo's comeback against Sega.
* Myst and The 7th Guest, both released in 1993, drove adoption of CD-ROM drives for personal computers.
* Virtua Fighter 2, Nights into Dreams, and Sakura Wars are the killer apps for the Sega Saturn.
** Euro 96 and Sega Rally Championship are major system-sellers for the Sega Saturn in the United Kingdom, with the latter becoming the fastest selling CD game.
** Die Hard Arcade and Fighters Megamix boosted the Sega Saturn's sales in the United States.
* Ridge Racer, Tekken, Wipeout, Tomb Raider, and Crash Bandicoot are the killer apps for the PlayStation. Tomb Raider was released for the Sega Saturn first and for MS-DOS at the same time, but the games contributed substantially to the original PlayStation's early success. See Blache Fabian & Lauren Fielder and NG Alphas.
** Final Fantasy VII is another killer app for the PlayStation. Computing Japan magazine said that it was largely responsible for the PlayStation's global installed base increasing 60% from 10 million units sold by November 1996 to 16 million units sold by May 1997.
* Super Mario 64 and GoldenEye 007 are the killer apps for the Nintendo 64.
* Virtua Fighter 3, Sonic Adventure, and SoulCalibur are the killer apps for the Dreamcast.
** NFL 2K is a killer app for the Dreamcast in the United States.
* Gran Turismo 3 and the Grand Theft Auto games are the killer apps for the PlayStation 2.
* Star Wars Rogue Squadron II: Rogue Leader, Super Smash Bros. Melee, and Super Mario Sunshine are the killer apps for the GameCube.
* Halo: Combat Evolved and Halo 2 are the killer apps for the Xbox, and the subsequent series entries became killer apps for the Xbox 360 and Xbox One.
** Many video game and technology critics call Xbox Live a more general killer app for the Xbox.
** Blue Dragon is a killer app for the Xbox 360 in Japan.
* Wii Sports is the killer app for the Wii.
* Metal Gear Solid 4: Guns of the Patriots boosted PlayStation 3 sales.
* Mario Kart 8 is a killer app for the Wii U in the UK.
* The Legend of Zelda: Breath of the Wild is a killer app for the Nintendo Switch.
* Half-Life: Alyx is a killer app for virtual reality headsets, as the first true AAA virtual reality game. Sales of VR headsets such as the Valve Index increased dramatically after its announcement, suggesting users bought the product specifically for the game.
* Microsoft Flight Simulator was called a killer app for Xbox Game Studios's Xbox Game Pass subscription, and the Xbox Series X/S.
* Pokémon games are killer apps for Nintendo handhelds, often topping the best-selling charts for whatever system they appear on.