BeforeInstallPromptEvent.prompt()

This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.

The prompt() method of the BeforeInstallPromptEvent interface allows a developer to show the install prompt at a time of their own choosing. 

Syntax

JavaScript
BeforeInstallPromptEvent.prompt()

Parameters

None.

Returns

An empty Promise.

Example

JavaScript
var isTooSoon = true;
window.addEventListener("beforeinstallprompt", function(e) {
  if (isTooSoon) {
    e.preventDefault(); // Prevents prompt display
    // Prompt later instead:
    setTimeout(function() {
      isTooSoon = false;
      e.prompt(); // Throws if called more than once or default not prevented
    }, 10000);
  }

  // The event was re-dispatched in response to our request
  // ...
});

Specifications

This method is not part of a specification.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 45.0 [1]        
Feature Android Android Webview Firefox Mobile (Gecko) Firefox OS IE Mobile Opera Mobile Safari Mobile Chrome for Android
Basic support No support 45.0 [1]           45.0 [1]

[1] Behind the flag: chrome://flags/#bypass-app-banner-engagement-checks

License

© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-us/docs/web/api/beforeinstallpromptevent/prompt

API BeforeInstallPromptEvent Experimental Method prompt Reference