Make a SIP call with an iPhone

by postbreak

Making a phone call over the internet is all the rage. Skype let you prank call anyone in the US for a year or so and with this article I’m going to show you how to make a SIP call using a jailbroken iPhone 3G and a few free applications. There are a few requirements for making VOIP calls on the iPhone and they include the following.

  • Jailbroken iPhone with backgrounder installed
  • Fring installed from the app store
  • GrandDialer from the app store
  • Account
  • Account

So if you have all of the above then congratulations, you can make free inbound and outbound calls over your 3G connection. Now I am going to show you how with those requirements combined you can make these calls.

First you need to go over to and download the application for your operating system. From there register for an account and you’re finished. Fire up the Grand Central website and click on “Phones”. Add a phone under the category “Gizmo”. You should be given a number after registering your gizmo account and simply place that into the number field. Save it and you’re finished with Grand Central.

Now we move over to the iPhone where things get a little complicated. First start Fring and go to Addons~>Sip~>Gizmo. Put your username and password in. Now you are finished with Fring.

Fire up GrandDialer and put your account information in under Settings. Click “Edit Numbers” and add your Gizmo number, this is the same number you put in the phone section of Grand Central. You are now finished. Open Fring and hold the home button down for a few seconds as backgrounder flags the application to stay open. You are ready to make a call. Open Grand Dialer and dial your number, hit Call, and then you’ll hear a ringing by Fring. Hit the home button and open Fring and accept the call. You will be connected by Grand Central to the number you are calling. It’s that simple.

Now lets recap how this works. Fring is running in the background with your Gizmo SIP account enabled. Inbound calls on that account are completely free. You dial a number with Grand Dialer which tells Grand Central’s servers to make a call to your Gizmo number. Since your Gizmo number is getting called Fring comes alive letting you know someone is calling you. When you pick up Grand Central acknowledges you have answered and connects you to the number you dialed originally. The call is placed and in about 7 seconds from dialing you hear the call being connected.

This is not a pretty solution but if you are inside a building with no cell service yet you have wifi it can be a life saver. This is also a way to cut back on minutes.

A few notes on SIP calls. There is a delay. This delay is not enough to kill the service but people on the other end have reported hearing themselves faintly. I would not use this service as a replacement to modern cellphone calls but it does come in handy sometimes.