Microsoft today announced that there will finally be a Fast ring for the Office Insider Program. It will be available for all platforms in which there is an existing Insider Program - including Windows, Mac, Windows Mobile (Office Mobile for PCs and phones), and Android - but it will also be coming to iOS.
While the part about iOS seems to be insignificant, this is the first time that the company has made a solid statement about Office Insider for iOS. The closest we've come is the Visio on iPad Insider Program, which was only announced a couple of weeks ago.
Microsoft says that the upcoming Fast ring builds are the same ones that employees have access to internally. The company says it's "best for Insiders who want to use the earliest preview builds to identify issues, provide feedback to help make Office great, and who don’t mind a bit of risk using unsupported builds."
That statement is important, as users should know what signing up for the Fast ring means. Even though it's not a full build of Windows 10, buggy software can still disrupt your work flow. We recommend that you don't use Office Insider Fast on your main machine.
Microsoft says that Office Insider Fast will be coming to Windows PCs, Macs, and Windows Mobile within the next few days, and Android and iOS will be "coming soon".
Source: Office Blogs