Now, our great international calling rates extend to any phone. Make any additional phone, including a mobile, an Extension at no extra charge and start saving money on international calls. All Vonage plans include a Vonage Extension. Call when you want, when it's convenient for you.
* Free and easy to set up
* Ability to extend to mobiles
* One convenient bill for all your calls
How to register your Extension phone:
1. Sign up for Vonage home service.
Current customers, skip to step 2.
2. Log in to your Vonage online account.
3. Select the Features tab, click the Extensions link, register one additional phone number from which you would like to make international calls and select a PIN.
How to make international calls using your Extensions:
1. Dial your access number from your registered phone.
2. Enter your PIN.
3. Dial the international destination number.
if you have the IPHONE app then you to dial the access number or enter PIN.
Read more here > http://www.vonage.com/features.....extensions