Window.onbeforeinstallprompt

Obsolete
This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.

The Window.onbeforeinstallprompt property is an event handler for processing a beforeinstallprompt, which is dispatched on devices when a user is about to be prompted to "install" a web application. Its associated event may be saved for later and used to prompt the user at a more suitable time. 

Syntax

window.addEventListener("beforeinstallprompt", function(event) { ... });
window.onbeforeinstallprompt = function(event) { ...};

Example

The following example uses the beforeinstallprompt event handler to make an install button operable, by using the event inside a click handler.

window.addEventListener("beforeinstallprompt", function(beforeInstallPromptEvent) {
  beforeInstallPromptEvent.preventDefault(); // Prevents immediate prompt display

  // Shows prompt after a user clicks an "install" button
  installButton.addEventListener("click", function(mouseEvent) {
    // you should not use the MouseEvent here, obviously
    beforeInstallPromptEvent.prompt();
  });

  installButton.hidden = false; // Make button operable
});

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
onbeforeinstallpromptChrome Full support YesEdge Full support ≤79Firefox ? IE ? Opera Full support YesSafari ? WebView Android Full support YesChrome Android Full support YesFirefox Android ? Opera Android Full support YesSafari iOS ? Samsung Internet Android Full support Yes

Legend

Full support  
Full support
Compatibility unknown  
Compatibility unknown

See Also