Voice calls and SMS can be pretty taxing on your monthly phone bill if you're a heavy user. If your current mobile plan comes with a bundled data package, perhaps it's time to make full use of that additional service.
But first, you'll have to download Viber, an app that utilizes your mobile data or a Wi-Fi connection to send text messages or make VoIP calls to your friends. While it was originally only available on Apple's iOS, the app has now moved on to the Google Android Market. Here's a quick video that explains the features that are found on Viber.
Both iOS and Android have a relatively high adoption rate amongst smartphone users, and this app makes it easier to conduct cross-platform communication. Besides being a free app, Viber takes a cue from Whatsapp and lets you call or text someone using Viber when you access their contacts from the phone's native address book.
Honestly, in the very near future, perhaps all you need is a mobile data plan from your telco to call or send text messages to your friends.
Source: GSM Arena