Although Windows 10 "Redstone 4" is not yet complete, Microsoft has already begun its first tests on Windows 10 "Redstone 5".
At 14 in February, Microsoft released two new test builds: Redstone 4 build 17101, and the first build of Redstone 5 (17604).
Fast Ring testers can access Redstone 4, while those in the "Skip Ahead" ring can try Redstone 5, though it's too early to notice any new features.
Microsoft officially announced a new preview program for Windows 10 applications along with the two new builds.
The new program allows Windows Insider testers to choose to preview individual applications instead of having to be part of the "Skip Ahead" ring to access the latest company app updates.
Insiders will be able to choose to have previews for Feedback Hub, Microsoft Photos, Microsoft Sticky Notes, Microsoft Tips, Paint 3D, Windows Alarms & Clock, Windows Calculator, Windows Camera, Windows Mixed Reality Viewer and Windows Voice Recorder.
To choose to preview an app, go to the app's "Settings" or "Information" page and click on the "Join preview" or "Leave preview" button.
Microsoft currently has a limited number of previews but will open more slots gradually. Internal collaborators already in the Skip Ahead ring do not have to choose to take these previews.
Back to Windows 10 now. In both trials, Microsoft made changes to Windows permissions, giving users more control over Universal Windows Platform applications that can now access the entire file system. Microsoft has made slight changes to the appearance of emoji, including 17101 and 17604.
Microsoft also added two new features to Windows 10 Pro for Workstations with the released demos:
A new energy system called Ultimate Performance, replacing all consumer consumer apps and games with productivity and business applications.
Η today's announcement of the company includes a long list of changes, fixes, and updates for 17101 and 17604.
Microsoft is expected to launch Redstone 4 around April 2018 and Redstone 5 around 2018 in October.