Telegram - Telegram is a messaging app with a focus on speed and security. It’s superfast, simple and free.
Signal - Fast, simple & secure messaging. Privacy that fits in your pocket.
Disa - Disa is your new messaging hub.
Skype - Stay in touch with your family and friends for free on Skype. Download Skype today to chat and call on desktop and mobile.
Unigram - The Telegram client for the Windows 10 platform, built by the community for the community.
Slack - A messaging app for teams who see through the Earth!