Evercontact - Your contacts always up to date and automatically with Evercontact.
Slack - A messaging app for teams who see through the Earth!
Pobuca Connect - Connect with your contacts.
9mCollab - Collaborate (efficiently) Conclude (fast) Contribute (in the knowledge base)
CONTACTBOX - CONTACTBOX combines the simplicity of an address book with effective functions of a CRM system.
Mattermost - Mattermost is an open source alternative to Slack.