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

The onconnecting event handler of the TelephonyCall interface is a reference to a function to be called to handle the Telephony API's connecting event.

This event occurs when the call has finished dialing but before the connection is made. The event handler is called with a CallEvent as its only parameter.


myCall.onconnecting = function() { ... };


// Telephony object
var tel = navigator.mozTelephony;

// Place a call
tel.dial("123456789").then(function(call) {

  call.onconnecting = function(e) {
    console.log('Your call to ' + + ' is connecting.');


Specification Status Comment
Web Telephony Draft Draft.

Browser compatibility

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

Supported in Firefox OS 1.0.1.

See also