The market opportunity for Office 365 is big enough without targeting businesses that aren't already Microsoft customers, Markezich says. "We don't want to force fit someone into a work style that they aren't comfortable with or doesn't best suit their purpose."
"This has been years in the making and blends many organic investments like bots and Office 365 with acquisitions like Skype and Yammer," Moorhead says. "If Microsoft can keep up with Slack's connectors and maintain their Office 365 pricing model, Slack could likely be at risk of decreased growth as they no longer have a giant utility lead."
The software maker says it has 85 million active paying Office 365 customers, and that massive install base should help the company quickly get the app into the hands of many working professionals. Microsoft Teams is now available to Office 365 enterprise and small business customers, in beta, for Android, iOS, Windows Phone and as a web app.
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