Application.Quit

static function Quit () : void

Description

Quits the player application. Quit is ignored in the editor or the web player.

IMPORTANT: In most cases termination of application under iOS should be left at the user discretion. Consult Apple's Technical Q&A qa1561 page for further details: http://developer.apple.com/iphone/library/qa/qa2008/qa1561.html

JavaScript
// Quits the player when the user hits escape
function Update () {
if (Input.GetKey ("escape")) {
Application.Quit();
}
}