Alternativa Formu za Slack z brezplačno licenco

• Slack
  Vse platforme Windows Mac Android iPhone Apple Watch iPad Android Tablet Web Self-Hosted Software as a Service (SaaS) Slack Apple Messages Apple TV Trello Microsoft Office Suite Atlassian Stash Google App Engine
• Brezplačna licenca
  Vsako dovoljenje Brezplačna licenca Open Source licenca Trgovsko dovoljenje