Anyone can use Sway so long as they have a Microsoft account -- there's no Office 365 subscription required. Business users who want to integrate Sway with their existing Office 365 subscription will likely have access to it unless their company is subscribed to an older plan that Microsoft no longer sells. (In that case, it's still possible for them to use the service with their personal account.)
The launch comes as Microsoft is gearing up for the release of Office 2016 this fall. The latest edition of the company's office suite is already available for Mac users with an Office 365 subscription, while Microsoft is still tweaking a public beta version of the apps for Windows.
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