Integration Opportunity:

The “fastest growing application in Microsoft history,” Microsoft Teams is a unified communications platform (chat, video, phone calls, file collaboration) that is native to the Office 365 suite and now used by over 13 million daily active users. Its robust developer platform and high traffic AppSource marketplace make it a best-in-class integration opportunity.

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Microsoft Teams App Dimensions


  • 10M to 50M
  • Very Small (Under $1M)
  • Small (Under $10M)
  • Mid-Cap ($10M-$50M)
  • Enterprise ($50M-$500M)
  • Giants ($500M+)
  • External Marketplace
  • Inside App UI

Declared “the fastest growing app in Microsoft’s history,” Teams gained 13 million daily active users in less than two years, and is now significantly larger than Slack. Microsoft’s AppSource store features thousands of integrated ISVs, but the Teams-specific marketplace is still quite small (under 300 apps). With over 160 million Office 365 users, the search volume on AppSource is reportedly +3 million unique users per month, in part because searching and learning about apps is very easily done from within the Team UI (Desktop and Browser). And finally, AppSource facilitates app monetization (for a fee).


  • Internal UI
  • Target App's UI
  • Point-to-Point

The Microsoft Teams developer platform offers several use cases and user experiences, including:

Search & Polling Bots- sending chat messages to groups and individual users, or allow users to query or converse with your app via chat responses, and take action on responses or alerts

Cards & Tabs- embed third party apps and/or allow external data to be displayed inside Teams and Channels

Connectors- sync data to/from Teams (i.e. adding/removing user data)

Task Modules- enable modal popup experiences that run your custom Javascript/HTML code

Calls & Meetings- interactive voice response (IVR), call control, and access to real-time audio and/or video streams for calls and meetings, including desktop and app sharing


  • Third Party

Publishing Cost: Microsoft Teams does not charge any fee to publish your App in their App Directory. If you choose to monetize through their AppSource store, a percentage fee may apply.

Code Hosting Cost: Microsoft Team’s platform facilitates some functions, but most of integration’s code will run on an independent third-party server like Azure, AWS, or Heroku. Left Hook may also need to build custom UI elements for user authentication, field mapping, and related implementation steps. These costs will scale depending on number of users and the amount of data moving between apps; for most SaaS companies, this secure infrastructure will cost between $50 and $200 per month. Contact us to explore these costs in greater detail.