Jostle Alternatives for Android

Slack is a cloud-based team collaboration tool.

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

eXo Platform is an open source, standard-based, Enterprise Social Collaboration Platform.

Bitrix24 is a free (for small businesses) social enterprise platform.

Podio is a cloud-based collaboration service.

Whaller allows teams and organizations to create their own internal social networks, meaning no adverts and no data exploitation.

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

Yammer is a freemium enterprise social networking service used for private communication within organizations.

Dialog Messenger is a handy and feature-rich enterprise multi-device messenger available for server or cloud.

Azendoo is a project management & team collaboration platform.