There's an app for that

Delta writer Damini Purkayastha spends a lot of time on the phone with her friends and family back home. If you’re spending a lot of money on international calls, she recommends Viber, a VOIP calling app for smart phones. If you have smart phone and a decent mobile date package, then everything else is pretty much free. SMSes, surfing, emailing and even international phone calls.

Unlike other calling apps, this doesn’t require a separate email account; instead it is registered to your phone number through a simple code sent via SMS. You can even download on a tablet and register it to your regular phone number.

Unlike Skype or Google Talk, Viber doesn’t need a separate contact list, instead it automatically links to your phone book and shows you which of your contacts have the app (and can hence be called for free!) While this app also lets you send free SMSes and share images, its primary functionality is calling, which means there are far less call drops. The app is light, needs minimal background data so it’s easy on your data plan and the simple interface uses little battery.