https://volt.ws/

• slack
• skype
• discord
• xmpp
• client

http://rambox.pro/

• skype
• whatsapp
• messenger
• slack

https://freeter.io/

• developer
• dashboard
• trello
• slack
• organizer

http://www.mattermost.org/

• slack
• alternative
• opensource
• self-hosted
• chat
• messaging
• IT
• golang
• react

https://zulip.org/

• chat
• client
• slack
• python
• dropbox

http://blog.trello.com/tips-for-managing-a-remote-team/

• management
• remote
• team
• trello
• "google drive"
• slack