VoiPax

VoiPax is a service that lets you call the world for free or for very cheap rates straight any PC or standard telephone set. You can either download the VoiPax client (Windows only) or take advantage of the VoiPax Instant service from your regular phone to make and receive calls. You only need to register to the site and have a fast Internet connection. By using the Windows client you can also send / receive SMS text messages. Call forwarding, calling ID, call waiting and three-way calling are all supported. No mobile app, nor voicemail are available.

VoiPax call rates

http://www.voipax.com/

Lingo

Lingo is a VoIP service that allows you to make phone calls from your PC, mobile device or landline phone to any part of the world. From your landline, just register for free to the service and then connect the Lingo adapter to your standard phone and high-speed internet router. From your mobile, register to Lingo and download the free app for Android and BlackBerry (iPhone is not supported) to start calling. Voicemail, call forwarding, calling ID and three-way calling are all supported features. You can also receive calls, but SMS service is not available.

Lingo call rates

http://www.lingo.com/

JAJAH

JAJAH is a free service that allows you to make and receive low cost phone calls to any mobile or landline in any part of the world. You can either access JAJAH from the web, from one of the many plugins available, from your landline phone or mobile device. You can receive phone calls using a dedicated number that JAJAH provides you and also send and receive SMS messages (fee applies). Voicemail is not supported. Enterprise and white-label solutions for business are also available.

JAJAH call rates

http://www.jajah.com/

ooVoo

ooVoo is a free web conferencing service that you can also use to make and receive phone calls to any mobile or landline across the planet for very low rates. The software is available for Windows and Mac. No Linux or mobile version are available. Two-way video conferencing is free to use, while video conferencing with up to 6 participants is priced at $0.10/min per participant. ooVoo also allows you to send and receive SMS text messages (fee applies) and supports text chat, call recording and file sharing. No voicemail is available.

ooVoo call rates

http://www.oovoo.com/

Skype

Skype is a free online conferencing service that allows you to make and receive international phone calls to / from any computer or mobile phone. The software is available for Windows, Mac, Linux and all recent mobile phones like the iPhone, most BlackBerry models and all Android-based and Windows 7 phones. Skype to Skype calls and video calls are always free and Skype To Go allows you to place international calls at domestic rates from any mobile or landline phone. You can also send and receive SMS text messages (fee applies). When you are disconnected or unavailable, all unanswered calls are saved in your personal voicemail. Two-way and multi-party video conferencing up to five people is supported, as well as text chatting, file sharing and screen-sharing.

Skype call rates

http://www.skype.com

iCall

iCall is a service that allows you to place and receive free calls to any mobile or landline of any world country. iCall is available as a web-based application, as a mobile app for the iPhone, or as a Windows desktop software tool. Free calls made from your computer have a five-minute limit, while longer calls made from your PC or iPhone are billed in a pay-as you-go fashion. All unanswered calls are collected in your personal voicemail. The new desktop version of iCall is currently in public beta and is available also for Mac and Linux computers. iCall 7 Beta works also as a multi-protocol IM application that supports all major chat networks like AIM, Live Messenger, Yahoo! Messenger, Facebook, ICQ, and others. iCall cannot send nor receive SMS test messages.

iCall call rates

http://www.icall.com/

VoxOx

VoxOx is a free multi-protocol instant messaging service and online conferencing software that allows you to make (and receive) cheap phone calls to / from landlines and mobiles. The software is available for Windows and Mac. Two-way and three-way calls and video calls with VoxOx users are always free. You can also send and receive SMS text messages (fee applies) and also send and receive fax (free of charge). When you are disconnected or unavailable, all unanswered calls will be saved in your personal voicemail. Other features are: call forwarding, ringtone customization, text chatting, file sharing, social media integration, and more. No mobile version of VoxOx is available.

VoxOx call rates

http://www.voxox.com/

Vyke

Vyke is a web-based service that allows you to save money on local and international calls. Vyke is available as a mobile app, as a Windows-based software or for any landline phone. You can also use Vyke, both from your PC and mobile phone, to send and receive SMS text messages (fee applies). When you sign-up to the service, Vyke gifts you with $1 credit to start making your phone calls. A business version of Vyke is also available with call rates starting at 1p/min. You cannot receive calls using Vyke and voicemail is not available.

Vyke call rates

http://www.vyke.com/

Yahoo! Voice

Yahoo! Voice is an additional feature of Yahoo! Messenger that allows you to make and receive calls to / from any part of the world at low rates using JAJAH technology. Yahoo! Messenger is available for Windows, Mac, iPhone and also works as a web-based application. Yahoo! Voice supports SMS sending and reception (fee applies) and also free voicemail for Win and Mac versions. Calls and video calls among Yahoo! Messenger users are always free. Other features are: instant messaging, file sharing, call forwarding (iPhone and web-based versions excluded), and more.

Yahoo! Voice call rates

http://voice.yahoo.jajah.com/

FriendCaller

FriendCaller is a Java-based service that lets you make free Internet calls and low cost international calls from any web browser to any mobile or landline. You just have to send a Call-me link from FriendCaller.com website to a friend and have him call you back. You can send Call-me links via email, social media, IM, place a link on your profile, or any other way you like. FriendCaller is also available as a mobile app for the iPhone and all Android-based mobile phones. No SMS, nor voicemail are available.

FriendCaller call rates

http://www.friendcaller.com/