Slack introduces a new app to integrate Microsoft Teams calling features and launches VoIP phone integration with Zoom, WebEx, Jabber, and more
You can now launch a Microsoft Teams call directly from Slack — Slack is launching a new app to integrate Microsoft Teams calling features into its chat app today.
Context & Ripple Effects
Microsoft built Teams explicitly to unseat Slack — it was previewed internally as a Slack competitor with channels, video calls, and meeting scheduling before launching bundled with Office 365 in November 2016. Slack's answer has been to absorb the rival's surface area rather than fight feature-for-feature: it already hosted Skype calls from within Slack back in early 2016 and deepened its Office tie-ins with full PowerPoint previews and Outlook/OneDrive apps in 2019.
Today's move extends that playbook to calling itself: a new app lets users launch Microsoft Teams calls directly from Slack, alongside VoIP phone integrations with Zoom, WebEx, and Jabber. The strategic read is that Slack is conceding nothing on chat while positioning itself as the neutral switchboard for whatever calling stack an enterprise already runs.
First-order effects
- Slack users on mixed Microsoft shops no longer need to leave Slack to start a Teams call, removing one of the main workflow reasons to migrate to Teams outright.
Second-order effects
- Zoom, WebEx, and Jabber gain a distribution channel inside Slack's installed base, while Microsoft faces a choice between blocking the integration and letting Teams calling reach users who never adopted Teams chat.
Third-order effects
- If chat clients keep absorbing rivals' calling features, voice becomes a commodity routed through whichever messaging hub wins the desktop — with platform lock-in shifting from the call itself to the conversation layer around it.
The trend: Workplace chat platforms are evolving from walled-garden competitors into interoperable hubs that host each other's calling features, commoditizing voice in the process.