There are several apps for Android today that allow making calls using the phone's data connection. Here are five hand-picked apps that not only provide quality VoIP services, but also bundle a slew of other interesting features.
Skype, a pioneer of Voice over IP services, is a dominant player even on the Android platform. After registering for Skype services, users can add contacts and engage in free Skype to Skype client calls over WiFi networks for better audio quality.
Also, the service offers free Skype-to-Skype video calls. Users can make relatively cheap international calls by buying Skype credit. Engage in instant messaging, photo exchanging and voice calls over WiFi as well as 3G networks. Get the Skype App for Android smartphones from Google Play store.