This feature is not on a current W3C standards track, but it is supported on the Firefox OS platform. Although implementations may change in the future and it is not supported widely across browsers, it is suitable for use in code dedicated to Firefox OS apps.
MozAlarmsManager object you can use to schedule notifications or applications to be started at a specific time.
var alarms = window.navigator.mozAlarms;
navigator.mozAlarms is a
|Web Alarms API||Working Draft||Defines the extention for the
|Feature||Chrome||Firefox (Gecko)||Internet Explorer||Opera||Safari (WebKit)|
|Basic support||Not supported||Not supported||Not supported||Not supported||Not supported|
|Feature||Android||Firefox OS||Firefox Mobile (Gecko)||IE Mobile||Opera Mobile||Safari Mobile|
|Basic support||Not supported||1.0||Not supported||Not supported||Not supported||Not supported|
 This API is currently available on Firefox OS only for any installed applications. The current specification for this API is not considered stable enough to unprefix the API yet.