Viber Media has released its popular free VoIP calling app Viber for Android phone and can be downloaded free at Android Market. Viber was popular on iPhone, which lets you make free phone calls and send free text messages to other users that have Viber installed.
The best part of this app is that it does not require any login. It automatically checks if your contacts are there on Viber. Moreover, Viber is completely free and it does not contain any annoying ads.
To make a free call or send free text message to anywhere in the world, all you need is a 3G or Wi-Fi connection and Viber installed on your phone. (Of course, your contacts should have Viber on their phone).
You can download Viber for Android at Market here.