It looks like Microsoft is letting free its brand-new two-factor authentication (2FA) app for Windows 10 Mobile. Microsoft Authenticator has been listed in the Store for a while but only as a private beta for internal testing. Now, it looks like anybody can download and start using with the one caveat that you need to be on Windows 10 Mobile 'Redstone' and not Production or Release Preview Insider rings.
The app, which is still in development, will eventually let users unlock their Windows 10 PCs running the Anniversary Update via a Bluetooth (aka presence) detection. That feature is not yet available as far as we can tell.
Full story from the WindowsCentral blog...