There are several VoIP apps for Android that provide free calling over an internet connection, Wi-Fi, or a data plan. One popular VoIP app is Viber. Viber does not require a username and password. It uses your mobile phone number and integrates it with your contacts list. Learn how to install Viber on Android devices running Android 4.1 or later.
To install Viber on an Android phone:
On your Android device, open Google Play and search for Viber to go to the Viber app page.
Tap Install to automatically download and install the app.
