Glip is fully searchable, real-time group chat; video chat, task management, file sharing app.

Mattermost is an open source, private cloud Slack-alternative, Workplace messaging for web, PCs and phones. MIT-licensed.

Flock is a communication app for teams. Packed with tons of productivity features, Flock drives efficiency and boosts speed of execution.

Dapulse is a smart collaboration and communication app you can use to get your team members working in sync in one place.

TribeScale is an All-in-One platform to coordinate your team around what really matters - communication, goals, decisions, tasks and results.

Mavenlink is an advanced project management, task collaboration, resource allocation, work management and professional services automation platform.

Hubgets provides chat, voice and video turning team communication.