Windows 10 Redstone will be the next major update after Spring Creators Update. It's development is already underway and expected to release this fall 2018.
Update 01 Sep 2018: Microsoft has officially announced Redstone 5 to be called as Windows 10 October Update.
What's New in Redstone 5 Features
It is a feature which lets you copy text or document from one device and save the data in cloud for pasting on another device. This is not limited to Windows 10 only but also will work across iOS and Android devices too. It is being said that Microsoft acquired SwiftKey will be put into use for cross-platform integration.
Sets (Tabbed Apps)
Few insiders of Redstone 4 were able to test this feature during the development phase. It is supposed to ship with Redstone 5 where everyone should get their hands on. Sets allow to create group of apps under a same window just like we use tabs for different webpages in web browser. Not just websites, but now you would be able to take this feature forward to Word, PowerPoint and few more apps. Moreover, a group or set could be shared across devices using the Timeline feature.
Once released, this would be a revolutionary step towards productivity and mark a significant change in the way we use PC today.
Just like we have notification center on Android phones, Microsoft is working on similar concept to bring most used settings and functions into one pop window called Control Center. The motive of this development is to bring all important system toggles and quick actions at one place. This area will have functions like WiFi, Focus Assist, Night Light and Brightness slider.
Immersive Search Experience
Search box is likely to be taken away from Cortana. New search UI is a search bar in the middle of screen which lets you search document, files, web information (via Bing) and access Settings too. If you are aware about Spotlight search feature of Mac OS, then you might say that this one is
copied inspired from Macintosh.
This feature can be enabled on Preview builds of Spring Creators Update by tweaking a registry key called as ImmersiveSearch.
Let us know what are you expecting in upcoming Redstone 5 build of Windows 10.