Digsby

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Google Hangouts

Pidgin is a chat application which lets you log into accounts on multiple chat networks simultaneously. Pidgin is developed and released fully free and open-source and provides a plugin architecture that allow anyone to build extensions and connections to new networks and third-party services.

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ICQ is the oldest cross-platform messenger and VoIP client. It was originally developed by the Israeli company Mirabilis in 1996, later sold to AOL in 1998. With ICQ you can stay connected with friends, family and co-workers. ICQ provides instant messaging andcan conver audio messages to text.

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Slack is a new way to communicate with your team in a faster, better organized, and more secure than email. The software is designed for business looking to improve their communication work flow. Slack offers features like persistent chat rooms organized by topic, private groups, and direct messaging that is built for teamwork.

Skype is a telecommunications application that specialize in providing video chat and voice calls between computers, tablets, mobile devices and consoles. The software allows you to connect with friends and business colleges worldwide. Skype provides free online calls, messaging, affordable international calling to mobiles or landlines and Skype for Business for effective collaboration among teams.