Windows 10 Fall Creators Update will bring a new Timeline feature that will offer a historical view of everything that you do on your devices.
Microsoft says "Timeline allows users to jump back in time with a visual timeline that displays what a user was doing previously and easily hop back into files, apps, and websites as if it was real time."
Built-in Windows 10 apps will leverage the Microsoft Graph to automatically log your activities, and third-party developers will also be able to use the Activity APIs to create engagement records as users interact with their applications. Developers will be able to customise how these activities are visualised in the Timeline by attaching an adaptive card to the activity. Android and iOS developers will be able to use the Project Rome SDK to achieve the same effect with their apps, which means your Timeline will also include activities you do on mobile devices.
The Timeline view will also be available on Android and iOS devices via the Cortana app, which now also offers the ability to pick up where you left off on other devices. Microsoft is also making it easy to copy text on one device and pasting on another.
Disclosure: Microsoft sponsored the correspondent's flights and hotel in Seattle for Build 2017.