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This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.

In the Open Web apps JavaScript API, an App object is a JavaScript object that represents an app that is or could be installed in the user's app repository.


Name Description Type
manifest The currently stored instance of the manifest of the app. object
manifestURL Where the manifest was found. string
origin The origin of the app (protocol, host, and optional port number). For example: string
installOrigin The origin of the site that triggered the installation of the app. string
installTime The time that the app was installed. This is generated using Date().getTime(), represented as the number of milliseconds since midnight of January 1st, 1970. integer
receipts An object containing an array of one or more receipts. Each receipt is a string. If there are no receipts, this is null. object or null
state The enabled state of the current application. enabled or disabled


Method Description
addReceipt() Adds a receipt to the app after an in-app purchase has been made.
launch() Launches the application. Does not return any value.

Check to see if the app has been updated. Returns a DOMRequest object.

For packaged apps: check for updates and mark it as downloadavailable if needed.

For hosted apps: check for updates on app manifest and application cache and update it if needed.

removeReceipt() Removes a receipt from the app after an in-app purchase has been cancelled.
replaceReceipt() Replaces one receipt with another.

Example App object

  manifest: {
    name: "Add-on Builder",
    default_locale: "en",
    installs_allowed_from: [
    description: "Add-on Builder makes it easy to write, build and test Firefox extensions using common web technologies.",
    version: "",
    developer: {
      url: "",
      name: "Mozilla Flightdeck Team"
  origin: "",
  installTime: 1321986882773,
  installOrigin: "",
  receipts: ["h0dHBzOi8v (most of receipt removed here) Tg2ODtkUp"]

Document Tags and Contributors

Last updated by: chrisdavidmills,