If you are looking for an alternative to Viber or Whatsapp Messenger, to make free calls and send messages from your Android Device, you can switch to the LINE Free Calls & Messages app. LINE regroups over 700 million user all over the world and it is available for the different mobile platforms (iOS, Windows Phone, Android) as well as for PC and MAC.
Features of LINE
Free voice and video calls.
Sharing of photos, videos, location data and voice messages