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Google Hangouts

WeChat connects a billion people with voice calls, video calls, photo sharing, chats and payments. The multi-purpose application is developed by the Chinese company Tencent and is and in China, it is described as "the app for everything". WeChat is primarily developed for the mobile consumer, but is also avalible on desktop and in the browser.

Facebook Messenger is a free standalone chat application that is well integrated with the social network, Facebook. With Facebook Messenger you can stay in contact with friends and family, and other contacts from Facebook. The applicaiton has a ton of built-in features that make communication fun and engaging. Send images, gifs, video messages, voice notes, and stickers or share content from around the web. Facebook Messenger automatically syncs with your Facebook contacts without the need of adding phone numbers or identification manually.

A mobile group messaging app developed and owned by Microsoft. GroupMe was first launched in 2010, today the application has over 12 million registered users that engage in group communication. The application makes it easy to stay in touch with those who really matter to you, and to do so in groups.

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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.