This API is available on Firefox OS for internal applications only.

The active read-only property of the Telephony interface returns a TelephonyCall object indicating the call that is currently active. The active call is the one that is currently receiving input from the microphone, or tones generated by calls to the Telephony.startTone() method.


var activeCall =;


A TelephonyCall object representing the currently active call.


// Telephony object
var tel = navigator.mozTelephony;

// Receive a call
tel.onincoming = function (e) {
  var incomingCall =;

  // Answer the call

// should return the call referenced in the above function
var activeCall =;


Specification Status Comment
Web Telephony Draft Draft

Browser compatibility

For obvious reasons, support is primarily expected on mobile browsers.

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support No support No support No support No support No support
Feature Android Firefox Mobile (Gecko) Firefox OS (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support No support 12.0 (12.0) 1.0.1 No support No support No support

See also

Document Tags and Contributors

 Contributors to this page: chrisdavidmills, teoli, fscholz, MHasan, kscarfone, Jeremie, Sheppy
 Last updated by: chrisdavidmills,