I have been using Viber on my foreign travels and am pleased with it.  Just remember you have to make calls to someone who already has Viber.  If they don’t you will be charged.

Download before you leave and get your family and friends to download as well.  The cool thing is you don’t have to add contacts.  Viber automatically knows who on your contact list has Viber and it will bring those contacts up when you click contacts in Viber.

Click here to read very important explanation about when a call is free or when there is a charge.  Very helpful information.

Here is information from their website:

Viber for iOS
Viber for iOS lets you use your iPhone to make free calls and send free text and photo messages to other Viber users, on any device, network and country! 

With Viber, your contacts on your device are also your Viber contacts, because Viber automatically detects your contacts who already have Viber. All you need to do is click on a name and start talking. No invites. No hassle. 

Viber’s user-friendly interface lets you easily perform calls and send messages. You will also be able to change your profile pic, see which of your phone contacts already has Viber and who else has just joined. 

  • Best-quality VoIP calls using 3G or Wi-Fi
  • Free text and photo messages with location-sharing
  • Group messaging with up to 15 friends
  • No registration, passwords or invitations required
* Calls and messages may use your data plan
Visit the AppStore, look up Viber, tap and start talking! It’s free!